bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of the Fibrosis and Angiogenesis Promoter SPARC/Osteonectin in Human Adipose Tissue by Weight Change, Leptin, Insulin, and Glucose
Authors: Kos Katrina , Wong Steve , Tan Bee , Gummesson Anders , Jernas Margareta , Franck Niclas , Kerrigan David , Nystrom Fredrik H. , Carlsson Lena M.S. , Randeva Harpal S. , Pinkney Jonathan H. , Wilding John P.H.
Published: June 2009

OBJECTIVE

Matricellular Secreted Protein, Acidic and Rich in Cysteine (SPARC), originally discovered in bone as osteonectin, is a mediator of collagen deposition and promotes fibrosis. Adipose tissue collagen has recently been found to be linked with metabolic dysregulation. Therefore, we tested the hypothesis that SPARC in human adipose tissue is influenced by glucose metabolism and adipokines.

RESEARCH DESIGN AND METHODS

Serum and adipose tissue biopsies were obtained from morbidly obese nondiabetic subjects undergoing bariatric surgery and lean control subjects for analysis of metabolic markers, SPARC, and various cytokines (RT-PCR). Additionally, 24 obese subjects underwent a very-low-calorie diet of 1,883 kJ (450 kcal)/day for 16 weeks and serial subcutaneous-abdominal-adipose tissue (SCAT) biopsies (weight loss: 28 ± 3.7 kg). Another six lean subjects underwent fast-food–based hyperalimentation for 4 weeks (weight gain: 7.2 ± 1.6 kg). Finally, visceral adipose tissue explants were cultured with recombinant leptin, insulin, and glucose, and SPARC mRNA and protein expression determined by Western blot analyses.

RESULTS

SPARC expression in human adipose tissue correlated with fat mass and was higher in SCAT. Weight loss induced by very-low-calorie diet lowered SPARC expression by 33% and increased by 30% in adipose tissue of subjects gaining weight after a fast-food diet. SPARC expression was correlated with leptin independent of fat mass and correlated with homeostasis model assessment–insulin resistance. In vitro experiments showed that leptin and insulin potently increased SPARC production dose dependently in visceral adipose tissue explants, while glucose decreased SPARC protein.

CONCLUSIONS

Our data suggest that SPARC expression is predominant in subcutaneous fat and its expression and secretion in adipose tissue are influenced by fat mass, leptin, insulin, and glucose. The profibrotic effects of SPARC may contribute to metabolic dysregulation in obesity.
Effects of Differing Antecedent Increases of Plasma Cortisol on Counterregulatory Responses During Subsequent Exercise in Type 1 Diabetes
Authors: Bao Shichun , Briscoe Vanessa J. , Tate Donna B. , Davis Stephen N.
Published: June 2009

OBJECTIVE

Antecedent hypoglycemia can blunt neuroendocrine and autonomic nervous system responses to next-day exercise in type 1 diabetes. The aim of this study was to determine whether antecedent increase of plasma cortisol is a mechanism responsible for this finding.

RESEARCH DESIGN AND METHODS

For this study, 22 type 1 diabetic subjects (11 men and 11 women, age 27 ± 2 years, BMI 24 ± 1 kg/m2, A1C 7.9 ± 0.2%) underwent four separate randomized 2-day protocols, with overnight normalization of blood glucose. Day 1 consisted of morning and afternoon 2-h hyperinsulinemic- (9 pmol · kg−1 · min−1) euglycemic clamps (5.1 mmol/l), hypoglycemic clamps (2.9 mmol/l), or euglycemic clamps with a physiologic low-dose intravenous infusion of cortisol to reproduce levels found during hypoglycemia or a high-dose infusion, which resulted in further twofold greater elevations of plasma cortisol. Day 2 consisted of 90-min euglycemic cycling exercise at 50% Vo2max.

RESULTS

During exercise, glucose levels were equivalently clamped at 5.1 ± 0.1 mmol/l and insulin was allowed to fall to similar levels. Glucagon, growth hormone, epinephrine, norepinephrine, and pancreatic polypeptide responses during day 2 exercise were significantly blunted following antecedent hypoglycemia, low- and high-dose cortisol, compared with antecedent euglycemia. Endogenous glucose production and lipolysis were also significantly reduced following day 1 low- and high-dose cortisol.

CONCLUSIONS

Antecedent physiologic increases in cortisol (equivalent to levels occurring during hypoglycemia) resulted in blunted neuroendocrine, autonomic nervous system, and metabolic counterregulatory responses during subsequent exercise in subjects with type 1 diabetes. These data suggest that prior elevations of cortisol may play a role in the development of exercise-related counterregulatory failure in those with type 1 diabetes.
Low HDL Cholesterol Is Associated With the Risk of Stroke in Elderly Diabetic Individuals
Authors: Hayashi Toshio , Kawashima Seinosuke , Itoh Hideki , Yamada Nobuhiro , Sone Hirohito , Watanabe Hiroshi , Hattori Yoshiyuki , Ohrui Takashi , Yokote Koutaro , Nomura Hideki , Umegaki Hiroyuki , Iguchi Akihisa
Published: June 2009

OBJECTIVE

To clarify the relationship between lipid levels and ischemic heart disease (IHD) and cerebrovascular disease (CVD) in diabetic individuals.

RESEARCH DESIGN AND METHODS

The Japan Cholesterol and Diabetes Mellitus Study is a prospective cohort study of 4,014 type 2 diabetic patients (1,936 women; mean ± SD age 67.4 ± 9.5 years). Lipid and glucose levels and other factors were investigated in relation to occurrence of IHD or CVD.

RESULTS

IHD and CVD occurred in 1.59 and 1.43% of participants, respectively, over a 2-year period. The relation of lower HDL or higher LDL cholesterol to occurrence of IHD in subjects <65 years old was significant. Lower HDL cholesterol was also significantly related to CVD in subjects ≥65 years old and especially in those >75 years old (n = 1,016; odds ratio 0.511 [95% CI 0.239–0.918]; P < 0.05). Stepwise multiple regression analysis with onset of CVD as a dependent variable showed the same result.

CONCLUSIONS

Lower HDL cholesterol is an important risk factor for not only IHD but also CVD, especially in diabetic elderly individuals.
Rehearsal Strategies during Motor-Sequence Learning in Old Age: Execution vs Motor Imagery
Authors: Stoter Arjan J. R. , Scherder Erik J. A. , Kamsma Yvo P. T. , Mulder Theo
Published: June 2009

Motor imagery and action-based rehearsal were compared during motor sequence-learning by young adults ( M = 25 yr., SD = 3) and aged adults ( M = 63 yr., SD = 7). General accuracy of aged adults was lower than that of young adults (F1,28 = 7.37, p = .01) even though working-memory capacity was equivalent in the two groups. Motor imagery and rehearsal by action increased accuracy in both age groups, compared with minimization of opportunity for rehearsal (F1,28 = 30.95, p < .001), but no interaction was found with age group, which suggests that young and aged adults were equally capable of motor imagery and action-based rehearsal. It was assumed that differences in performance between young and aged participants related to the formation of mental representations of sequences and integration of new elements into these representations rather than the capacity for motor imagery or rehearsal by action per se. The current study was exploratory and involved a relatively small sample of 15 participants per age group. Caution must be taken when considering the results.
Modified open-door cervical expansive laminoplasty for spondylotic myelopathy: operative technique, outcome, and predictors for gait improvement
Authors: Lee Thomas T. , Manzano Glen R. , Green Barth A.
Published: June 2009

✓ Twenty-five patients underwent an expansive cervical laminoplasty for nontraumatic cervical spondylosis with myelopathy during the period from June 1990 to November 1994, and all had a minimum of 18 months of follow-up review. The open-door laminoplasty procedure presently reported consisted of the same approach evaluated by Hirabayashi in 1977, except that the authors of this report used three rib allografts to anchor the “open door,” rather than spinous process sutures or autologous bone grafts. Posterior foraminotomies and decompression were performed in patients with clinical radiculopathy and radiographic evidence of foraminal stenosis.

Preoperatively, gait disturbance was present in all patients. All 25 patients (100%) had long-tract signs on presentation. Nondermatomal upper-extremity symptoms (numbness, tingling, weakness, and pain) were quite common in this group of patients. Bowel, bladder, and/or sexual dysfunction was found in 13 (52%) of 25 patients. Preoperative radiographic studies showed a mean midline anteroposterior diameter spinal canal/vertebral body (SC/VB) ratio of 0.623 and a mean compression ratio (sagittal/lateral diameter ratio × 100%) of 37%.

This procedure was quite successful in relieving preoperative symptoms and few complications occurred. Gait disturbance was improved in 21 (84%) of 25 patients and hand numbness and tingling were improved in 13 (87%) of 15 patients. Bowel or bladder function improved in 10 (77%) of 13 patients. Radiculopathy, when present, was alleviated in all four patients after the decompressive procedure. The postoperative SC/VB ratio, as measured by plain lateral radiographs and/or computerized tomography scans, was improved to 0.871, a 38% improvement. In a comparison with the preoperative SC/VB ratio using the two-tailed t-test, alpha was less than 0.001. The compression ratio improved to 63% postoperatively, which yielded an alpha of less than 0.005 according to the two-tailed t-test. Only one postoperative complication, an anterior scalene syndrome, was encountered.

Various predictors of surgical outcome based on gait improvement were evaluated. Age greater than 60 years at the time of presentation, duration of symptoms more than 18 months prior to surgery, preoperative bowel or bladder dysfunction, and lower-extremity dysfunction were found to be associated with poorer surgical outcome. Even when these conditions were present, gait improvement was noted in at least 70% of the patients.
Histological interaction of cultured endothelial cells and endovascular embolic materials coated with extracellular matrix
Authors: Tamatani Shinichi , Ozawa Tsunenori , Minakawa Takashi , Takeuchi Shigekazu , Koike Tetsuo , Tanaka Ryuichi
Published: June 2009

✓ This study was undertaken to evaluate the histological reaction of cultured endothelial cells to endovascular embolic materials in vitro. Endothelial cells were isolated and cultured from a canine carotid artery. Embolic materials (platinum microcoils, polyvinyl alcohol particles, silicon balloons, or silk threads), either in their normal state or after having been coated with type 1 collagen, fibronectin, or laminin, were placed on endothelial cells and cocultured for 6, 12, and 24 hours and 2, 3, 7, 14, and 21 days. The cocultures were investigated histologically using a scanning electron microscope. Endothelial cells were not found on any uncoated embolic materials, even at 21 days. On the materials coated with fibronectin or laminin, endothelial cells began to proliferate in 7 days, covering the materials extensively in 14 days. On the other hand, endothelial cells began to proliferate on the collagen-coated materials in 3 days, covering them extensively in 7 days and reaching confluence with a cobblestone pattern in 21 days. The densities of endothelial cells on collagen-coated materials were much higher than those observed on the materials coated with other extracellular matrices. Future advantages of the clinical use of collagen-coated embolic materials in interventional treatment are discussed.
Activation of complement by tissue plasminogen activator, but not acute cerebral ischemia, in a rabbit model of thromboembolic stroke
Authors: Bednar Martin M. , Gross Cordell E. , Russell Sheila R. , Short David , Giclas Patricia C.
Published: June 2009

✓ Although complement activation is associated with tissue injury during inflammatory and ischemic states, complement activation in states of acute cerebral ischemia before and after administration of tissue plasminogen activator (TPA) has not yet been examined and is the focus of this investigation.

Twenty-four New Zealand White rabbits weighing 3 to 3.5 kg were used for this study. Of these, 20 were subjected to intracranial autologous clot embolization via the internal carotid artery. Three hours postembolization, rabbits received an intravenous infusion of TPA (6.3 mg/kg, 20% bolus with the remainder infused over a 2-hour interval; 12 animals) or vehicle (eight animals). All animals were observed for a total of 7 or 8 hours postembolization. These two groups were compared to a cohort undergoing sham operation with subsequent TPA infusion (four animals). Plasma samples to quantify complement component C5 hemolytic activity (C5H5O) were obtained at the following time points: 30 minutes before and after clot embolization; 1 hour before and 1 hour after the initiation of therapy with TPA or vehicle and at the completion of the protocol; 7 to 8 hours after clot embolization.

The C5 activation was not detected as the result of acute cerebral ischemia. However, animals receiving TPA with or without concomitant clot embolization exhibited C5 activation as assessed by a reduction in C5 hemolytic function, both 1 hour after initiation of TPA infusion (78.7 ± 10.3% and 77.5 ± 9.9% of baseline value, respectively; mean ± standard error of the mean [SEM]) and at the end of the protocol, 2 hours after the completion of the TPA infusion (72.5 ± 8.8% and 53.3 ± 8.1%, respectively; mean ± SEM, p < 0.05, each group). This study supports the conclusion that TPA, but not acute cerebral ischemia, may activate the complement cascade in this rabbit model of thromboembolic stroke.
Regional parenchymal enhancement with mixed cavernous/venous malformations of the brain
Authors: Comey Christopher H. , Kondziolka Douglas , Yonas Howard
Published: June 2009

✓ With improvements in imaging technology, the detection of both cavernous malformations and venous malformations has increased markedly in recent years. Although much has been learned about the association of cavernous and venous malformations, important questions regarding the true nature of such a relationship remain unanswered. It has been proposed that certain venous malformations produce local venous hypertension with resultant microhemorrhage, growth factor release, and creation of cavernous malformations. The authors report on two patients with cerebellopontine venous malformations associated with cavernous malformations. Both patients demonstrated persistent regional parenchymal enhancement associated with the vascular malformations. In addition, both patients had significant clinical symptoms referable to the region of affected brain. This previously undescribed finding may represent an imaging correlate to the complex interaction among venous malformations, venous hypertension, and cavernous malformations.
Trigeminal neuralgia: a quantitative sensory perception threshold study in patients who had not undergone previous invasive procedures
Authors: Bowsher David , Miles John B. , Haggett Carol E. , Eldridge Paul R.
Published: June 2009

✓ The authors investigated 28 patients with “idiopathic” trigeminal neuralgia who had undergone no previous invasive procedures; together these patients had a total of 50 affected trigeminal divisions. Quantitative sensory perception thresholds were measured before operation. Preoperative measurements in the affected divisions indicated raised thresholds for touch (von Frey filaments) and temperature, but not for pinprick or heat pain, in agreement with the findings of Nurmikko. Only the tactile threshold was also significantly affected in the unaffected divisions on the affected side.

The authors discuss their findings in relation to the pathophysiology of trigeminal neuralgia, concluding that the origin of the condition is almost certainly central to the gasserian ganglion.
Chronic electrical stimulation of the gasserian ganglion for the relief of pain in a series of 34 patients
Authors: Taub Ethan , Munz Michael , Tasker Ronald R.
Published: June 2009

✓ The use of an implanted system for chronic electrical stimulation of the gasserian ganglion for relief of facial pain was described in 1980 by Meyerson and Håkansson. Between 1982 and 1995, the senior author (R.R.T.) performed gasserian ganglion stimulation in 34 patients for the relief of chronic medically intractable facial pain. The etiology of pain was peripheral damage to the trigeminal nerve in 22 patients (65%), central (stroke) damage in seven (21%), postherpetic neuralgia in four (12%), and unclassifiable cause in one (3%). All patients received a trial of transcutaneous stimulation (Stage I). Successful trials in 19 patients (56%) were followed by implantation of a permanent system (Stage II).

Trial and postimplantation stimulation were deemed successful when there was a reduction of pain by at least 50% whenever the stimulator was on. Success rates varied from five (71%) of seven patients for central pain to five (23%) of 22 for peripheral pain and none (0%) of four for postherpetic neuralgia. The median follow-up duration in successful cases was 22.5 months.

Infections occurred in seven patients, all of whom had undergone Stage II treatment. Infections were more frequent when the stimulating electrode from Stage I was left in place for Stage II (six [43%] of 14) than when completely new hardware was used and prophylactic antibiotic drugs were administered (one [20%] of five). Other complications included iatrogenic injury to the trigeminal nerve or ganglion in three cases (9%), transient diplopia in two (6%), increased pain in two (6%), and various technical problems in 10 (29%).

It is concluded that pain of central origin (stroke) is the type most likely to be relieved by this procedure. This finding is new, as the few other clinical series reported to date contain no patients with this type of pain. The risk of infection seems to be lower when completely new hardware is used for Stage II and prophylactic antibiotic drugs are administered.
Endovascular treatment of acutely ruptured and unruptured aneurysms of the basilar bifurcation
Authors: Raymond Jean , Roy Daniel , Bojanowski Michel , Moumdjian Robert , L'Espérance Georges
Published: June 2009

✓ The surgical treatment of basilar bifurcation aneurysms is difficult and the need for an alternative approach is frequently stated. To assess the efficacy and safety of endovascular treatment of aneurysms located at the basilar bifurcation, the authors prospectively studied angiographic results, clinical results, and complications in 31 patients treated with Guglielmi detachable coils (GDCs). Patients treated acutely after subarachnoid hemorrhage (SAH) were graded according to the Hunt and Hess classification and clinical outcome was determined at 1- and 6-month intervals according to the Glasgow Outcome Scale (GOS).

There were 18 women and 13 men, ranging in age from 34 to 67 years (mean age 48 years). Twenty-three were treated acutely after SAH. Clinical Hunt and Hess grades at presentation were as follows: Grade I, six patients; Grade II, three; Grade III, 11; Grade IV, two; and Grade V, one. The GOS score for the group of patients treated acutely was: GOS I, 18 patients; GOS II, III, and IV, one patient each; and GOS V, two patients. There were seven technical complications in this group, most often asymptomatic, but one patient died after aneurysm rupture during treatment and one had residual diplopia at 4 months. Eight patients were treated for incidental basilar bifurcation aneurysms. One technical complication with no neurological deficit occurred in this group of patients with incidental aneurysms.

Immediate angiographic results were considered to be satisfactory in 94% of patients, with complete obliteration in 42% and residual neck and dog ears in 52%. There was no bleeding episode after treatment during clinical follow-up periods ranging from 3 to 42 months (mean 15.5 months in 29 surviving patients). Angiographic results were available for 27 patients at 6 months and were as follows: 30% of the lesions were completely obliterated, 59% presented some residual neck, and 11% showed some opacification of the aneurysm sac. During the follow-up period of up to 42 months, a total of seven recurrences were noted, necessitating retreatment with GDCs in five patients.

Endovascular treatment of basilar bifurcation aneurysms prevented rebleeding and could be performed without clinically significant complications in 94% of patients. Clinical results after SAH compared favorably with surgical series. Morphological results appear less satisfactory, and long-term angiographic follow-up review is mandatory to detect recurrences.
Waveform changes due to conduction block and their underlying mechanism in spinal somatosensory evoked potential: a computer simulation
Authors: Tani Toshikazu , Ushida Takahiro , Yamamoto Hiroshi , Okuhara Yoshiyasu
Published: June 2009

✓ Based on a square-wave solid-angle analysis, a simplified mathematical model was produced for computing a sequence of potential change in a volume conductor generated by an impulse traveling along a nerve fiber. A conduction block was simulated as a phenomenon in which a depolarization wavefront stops traveling when it reaches a certain point, although the following repolarization wavefront continues to travel until it reaches the same point. The spinal somatosensory evoked potential (SSEP) was produced as an algebraic sum of simulated nerve fiber action potentials (NFAPs).

With a conduction block, an NFAP that was normally triphasic showed a positive—negative diphasic wave with reduced negativity at the point of the block, diphasic waves with enhanced negativity at points immediately preceding the block, and initial-positive waves alone or abolition of any wave at points beyond the block. The absence of their terminal-positive phases paradoxically enhanced the negative peak of the spinal SSEPs in a partial block that involved only the constituent fastest fibers, because phase cancellation of the phases between the terminal-positive phases of the fastest fibers and the negative phases of the slower fibers, which normally happens, failed to occur. At the points immediately preceding the block, the identical mechanism sustained the spinal SSEP enhancement even when every fiber was included in the block. The computer model predicted that localization of the precise site of conduction block can be achieved by demonstrating an abrupt reduction in the amplitude of the spinal SSEP, which is accompanied by an increased negative wave caudally and an enhanced monophasic positive wave rostrally.
The relationship of subarachnoid hemorrhage and the need for postoperative shunting
Authors: Vale Fernando L. , Bradley Edwin L. , Fisher Winfield S.
Published: June 2009

✓ The incidence of chronic hydrocephalus requiring shunting after aneurysmal subarachnoid hemorrhage (SAH) is not precisely known. The authors investigated whether the need for ventriculoperitoneal (VP) shunting can be predicted by initial Hunt and Hess grade or Fisher computerized tomography score. One hundred eight patients who presented with SAH and underwent 116 surgical procedures for aneurysm clipping were evaluated retrospectively to determine the incidence of chronic hydrocephalus. Chronic hydrocephalus was defined as clinically and radiographically demonstrated hydrocephalus that lasted 2 weeks or longer after the original hemorrhage and that required shunting. All SAH patients were managed in a similar fashion with induced hypervolemia, relative hemodilution, and hypertension complemented by a course of calcium channel blockers. The majority of patients underwent perioperative extracranial ventricular drainage to allow intraoperative brain relaxation and to assist intracranial pressure management. The overall mortality rate of the study group was 17%. Of the surviving patients, 20% underwent VP shunt placement secondary to chronic hydrocephalus. There were no statistically significant relationships between chronic hydrocephalus and patient age or gender, aneurysm type and size, or use of a perioperative drain. There was a high clinical correlation between chronic hydrocephalus and admission Hunt and Hess grades and Fisher grades (p < 0.05). All of the patients who survived a second bleeding episode and almost 46% of the patients who presented with intraventricular hemorrhage required placement of a VP shunt. The authors present predictive tables of chronic hydrocephalus based on the patient's admission Hunt and Hess grade and Fisher classification.
Normal perfusion pressure breakthrough: the role of capillaries
Authors: Sekhon Lali H. S. , Morgan Michael K. , Spence Ian
Published: June 2009

✓ Excision of human cerebral arteriovenous malformations (AVMs) can be complicated by postoperative edema and hemorrhage in adjacent brain tissue, despite the complete excision of the malformation. Various theories have purported to explain the hemodynamic basis for this predisposition, including disordered autoregulation causing “normal perfusion pressure breakthrough” and obstruction of venous drainage leading to “occlusive hyperemia.” This study did not evaluate the arterial or venous circulations in this scenario, but rather examined the capillaries in adjacent brain parenchyma for any structural deficiencies that would predispose the brain to the postoperative formation of edema and hemorrhage.

Arteriovenous fistulas (AVFs) were created surgically in the necks of 10 male Sprague—Dawley rats, which caused chronic cerebral hypoperfusion with a reduction in cerebral blood flow of between 25% and 50%. Ten age-matched animals were used as controls. Twenty-six weeks after AVF formation the animals were killed and perfusion fixed. Their brain tissue was prepared for light microscopic studies by staining for glial fibrillary acidic protein or for transmission electron microscopy. In the CA1 pyramidal cell region of the hippocampus, it was found that in the animals with AVFs there was increased capillary density and absent astrocytic foot processes in some of these vessels. It was concluded that these vessels had developed as a result of neovascularization in response to chronic cerebral ischemia and that their anatomical configuration made them prone to mechanical weakness and instability following the increase in perfusion pressure that occurs in adjacent brain parenchyma after AVM excision.

The authors believe that this study pinpoints a structural accompaniment to the hemodynamic changes that occur in brain tissue in the vicinity of cerebral AVMs that predispose these areas to the formation of edema and hemorrhage after AVM excision.
Isolation and characterization of human malignant glioma cells from histologically normal brain
Authors: Silbergeld Daniel L. , Chicoine Michael R.
Published: June 2009

✓ Brain invasion prevents complete surgical extirpation of malignant gliomas; however, invasive cells from distant, histologically normal brain previously have not been isolated, cultured, and characterized. To evaluate invasive human malignant glioma cells, the authors established cultures from gross tumor and histologically normal brain. Three men and one woman, with a mean age of 67 years, underwent two frontal and two temporal lobectomies for tumors, which yielded specimens of both gross tumor and histologically normal brain. Each specimen was acquired a minimum of 4 cm from the gross tumor. The specimens were split: a portion was sent for neuropathological evaluation (three glioblastomas multiforme and one oligodendroglioma) and a portion was used to establish cell lines. Morphologically, the specimens of gross tumor and histologically normal brain were identical in three of the four cell culture pairs. Histochemical staining characteristics were consistent both within each pair and when compared with the specimens sent for neuropathological evaluation. Cultures demonstrated anchorage-independent growth in soft agarose and neoplastic karyotypes. Growth rates in culture were greater for histologically normal brain than for gross tumor in three of the four culture pairs. Although the observed increases in growth rates of histologically normal brain cultures do not correlate with in vivo behavior, these findings corroborate the previously reported stem cell potential of invasive glioma cells. Using the radial dish assay, no significant differences in motility between cultures of gross tumor and histologically normal brain were found.

In summary, tumor cells were cultured from histologically normal brain acquired from a distance greater than 4 cm from the gross tumor, indicating the relative insensitivity of standard histopathological identification of invasive glioma cells (and hence the inadequacy of frozen-section evaluation of resection margins). Cell lines derived from gross tumor and histologically normal brain were usually histologically identical and demonstrated equivalent motility, but had different growth rates.
Tremor control after pallidotomy in patients with Parkinson's disease: correlation with microrecording findings
Authors: Taha Jamal M. , Favre Jacques , Baumann Thomas K. , Burchiel Kim J.
Published: June 2009

✓ The goals of this study were to analyze the effect of pallidotomy on parkinsonian tremor and to ascertain whether an association exists between microrecording findings and tremor outcome.

Forty-four patients with Parkinson's disease who had drug-induced dyskinesia, bradykinesia, rigidity, and tremor underwent posteroventral pallidotomy. Using a 1-µ-tip tungsten electrode, microrecordings were obtained through one to three tracts, starting 10 mm above the pallidal base. Tremor severity was measured on a patient-rated, 100-mm Visual Analog Scale (VAS), both preoperatively and 3 to 9 months (mean 6 months) postoperatively.

Preoperatively, tremor was rated as 50 mm or greater in 24 patients (55%) and as less than 25 mm in 13 patients (30%). Postoperatively, tremor was rated as 50 mm or greater in five patients (11%) and less than 25 mm in 29 patients (66%). The difference was significant (p = 0.0001). Four patients (9%) had no postoperative tremor. Tremor improved by at least 50% in eight (80%) of 10 patients in whom tremor-synchronous cells were recorded (Group A) and in 12 (35%) of 34 patients in whom tremor-synchronous cells were not recorded (Group B). This difference was significant (p = 0.03). Tremor improved by at least 50 mm in all (100%) of the seven Group A patients with severe (≥ 50 mm) preoperative tremor and in nine (53%) of 17 Group B patients with severe preoperative tremor. This difference was also significant (p = 0.05).

The authors proffer two conclusions: 1) after pallidotomy, tremor improves by at least 50% in two-thirds of patients with Parkinson's disease who have severe (≥ 50 mm on the VAS) preoperative tremor; and 2) better tremor control is obtained when tremor-synchronous cells are included in the lesion.
Electrophysiological investigation of hemifacial spasm after microvascular decompression: F waves of the facial muscles, blink reflexes, and abnormal muscle responses
Authors: Ishikawa Mami , Ohira Takayuki , Namiki Jun , Kobayashi Masato , Takase Moriichiro , Kawase Takeshi , Toya Shigeo
Published: June 2009

✓ In patients with hemifacial spasm, it has been said that the spasm is due to cross compression of the facial nerve by a blood vessel and that microvascular decompression (MVD) of the facial nerve is an effective treatment. The F waves, which result from backfiring of antidromically activated motor neurons of the facial motor nucleus, are indices of the excitability of the facial motor nucleus and are enhanced in patients with hemifacial spasm. Measuring blink reflexes and abnormal muscle responses (lateral spread), a characteristic sign of hemifacial spasm, has been used to investigate the mechanism of hemifacial spasm pathophysiologically. Thus the authors measured F waves of the facial muscle, blink reflexes, and abnormal muscle responses before and after MVD in patients suffering from hemifacial spasm to investigate the excitability of the facial motor nucleus and the course of the cure of hemifacial spasm after MVD. The authors obtained facial nerve—evoked electromyograms in 20 patients with hemifacial spasm before and after the MVD procedure. On the spasm side, the F waves and blink reflexes were enhanced preoperatively compared to those on the normal side and abnormal muscle responses were recorded in all patients. In 12 patients whose hemifacial spasm had not disappeared completely for 5.1 ± 1.7 (mean ± standard error) months following the MVD procedure, F waves were still enhanced significantly and abnormal muscle responses were still recordable, albeit at lower amplitude. Within 1 month after the hemifacial spasm had disappeared completely, F waves were still significantly enhanced in 17 patients and abnormal muscle responses were recorded in seven of 15 patients. Subsequently, the enhanced F waves and abnormal muscle responses disappeared completely. The authors' study supports the hypothesis that the cause of hemifacial spasm is hyperexcitability of the facial motor nucleus and suggests that additional surgery should not be performed for at least 2 years after MVD, because that period is necessary for the disappearance of the hyperexcitability of the facial motor nucleus.
Isolated straight sinus and deep cerebral venous thrombosis: successful treatment with local infusion of urokinase
Authors: Holder Chad A. , Bell D. Antonio , Lundell Andrea L. , Ulmer John L. , Glazier Steven S.
Published: June 2009

✓ A 23-year-old woman presented with headache and progressive lethargy. The diagnosis of isolated thrombosis of the straight sinus and of the deep cerebral venous system was established using cranial computerized tomography, magnetic resonance imaging, phase-contrast magnetic resonance venography, and cerebral angiography. Because of the rapid deterioration in the patient's clinical condition, the authors used direct transcatheter infusion of urokinase into the straight sinus. This treatment resulted in a successful outcome.
Dural inversion procedure for moyamoya disease
Authors: Dauser Robert C. , Tuite Gerald F. , McCluggage Charles W.
Published: June 2009

✓ A variety of surgical procedures have been proposed for the treatment of moyamoya disease, but few have used the potential of the middle meningeal artery to any great extent. During the period of spontaneous collateral formation, patients with this disease are at risk for the development of transient ischemic attacks and strokes. Surgical treatments aimed at increasing collateral flow to the brain from the external carotid system have included both direct and indirect anastomotic methods. In this report, the authors describe a technique that used the middle meningeal artery circulation as a source of collateral blood supply by inverting dural flaps that are located on a large meningeal vessel, allowing the richly vascularized outer dural surface to contact a large surface area of the ischemic cortex. An extensive degree of revascularization was observed.
Repositioning of the vertebral artery as treatment for neurovascular compression syndromes
Authors: Bejjani Ghassan K. , Sekhar Laligam N.
Published: June 2009

✓ Neurovascular compression syndromes are usually treated by interposing Teflon felt or padding or some other implant between the offending vessel and the nerves. However, this cannot be done in some cases in which ectatic vertebrobasilar arteries are involved. In these instances, alternative techniques must be used.

The authors report the use of a sling made of Prolene to reposition the vertebral artery in two patients with neurovascular compression disorder. The clinical results were gratifying, with complete resolution of the patients' symptoms.

Compression by large vessels is an uncommon but important source of neurovascular compression in patients with trigeminal neuralgia, hemifacial spasm, disabling positional vertigo, and, possibly, hypertension. The technique described may be useful to surgeons treating these problems.
Paradoxical effects of acute ethanolism in experimental brain injury
Authors: Kelly Daniel F. , Lee Stefan M. , Pinanong Patty A. , Hovda David A.
Published: June 2009

✓ Acute ethanol intoxication is a frequent complicating factor in human head injury, yet its impact on neurological outcome remains poorly defined. This study was undertaken to assess the effect of varying levels of preinjury ethanol on early postinjury mortality, recovery of motor function, and degree of neural degeneration after cortical contusion injury in the rat. Adult rats were pretrained on a beam-walking task, then randomized to one of five groups: low-dose ethanol and injury (1 g/kg, 16 animals); moderate-dose ethanol and injury (2.5 g/kg, 11 animals); high-dose ethanol and injury (3 g/kg, 17 animals); no ethanol and injury (nine animals); or ethanol and sham injury (seven animals). Forty minutes after intraperitoneal injection of ethanol or saline, the rats received a pneumatic piston—induced contusion injury of the left primary motor cortex. Their beam-walking ability was assessed daily for the next 7 days. At 4 weeks postinjury, the brains were sectioned and the dimensions of the cortical lesions were determined.

Preinjury ethanol administration was associated with an acute postinjury mortality rate of 29.5% (p < 0.05); the highest mortality rate (47.1%) occurred in the high-dose ethanol group, whereas no deaths occurred in the animals in the no ethanol or sham-injured groups (p < 0.01). However, injured animals receiving low- and moderate-dose ethanol had significantly less severe beam-walking impairment initially, and a more rapid return to normal beam-walking ability, compared to the no and high-dose ethanol groups (p < 0.05). Additionally, the mean lesion volumes were significantly smaller in the low- and moderate-dose ethanol treatment groups compared to the no and high-dose ethanol groups (23.2 ± 8 mm3 and 29 ± 6.7 mm3 vs. 52 ± 8.8 mm3 and 53.7 ± 10.9 mm3, respectively, p < 0.01). In this cortical contusion model, the presence of ethanol before injury appears to exert a potent neuroprotective effect when administered in low or moderate doses. This action is postulated to result from ethanol-induced inhibition of N-methyl-d-aspartate receptor-mediated excitotoxicity. The loss of neuroprotection and increased mortality rates observed with high-dose ethanol may be related to ethanol-induced hemodynamic and respiratory depression.
A burr hole button to secure the electrode cable in depth electrode placement
Authors: Kamiryo Toshifumi , Laws Edward R.
Published: June 2009

✓ A simple magnetic resonance imaging—compatible buttonlike device was devised to fix a depth electrode cable securely in the burr hole used for its insertion during surgery for depth electrode placement. The button is tightly fixed in the burr hole and it holds the cable without allowing protrusion or tension on the wound.
Stereotactic biopsy of nonpolar tumors in the dominant hemisphere: a prospective study of effects on language functions
Authors: Thomson Ann-Marie , Taylor Robert , Fraser Diane , Whittle Ian R.
Published: June 2009

✓ A prospective study of patients undergoing computerized tomography (CT)—guided stereotactic biopsy of nonpolar tumors in the dominant hemisphere was undertaken to determine if stereotactic biopsy caused a deterioration of language functions. Language was assessed using the Western Aphasia Battery (WAB) and the Boston Naming Test (BNT) before and after a biopsy sample was obtained. Of 16 patients studied, five (31%) were dysphasic preoperatively. After the biopsy the Aphasia Quotient (AQ), derived from the WAB, had significantly deteriorated in four (80%) of these patients, whereas in the fifth it remained relatively unchanged. One of these patients with an extensive infiltrating hemispheric oligoastrocytoma subsequently recovered normal language function after radiotherapy. In 10 of the 11 patients who had normal language function preoperatively there were no deleterious changes after biopsy in either the WAB subtest or BNT scores. In the other patient whose WAB score was normal preoperatively, there was a significant deterioration in postoperative AQ. This patient, who declined steroid therapy before and after biopsy, had a glioblastoma multiforme in Wernicke's area. A postoperative CT scan revealed no changes from what was shown on preoperative scan.

This clinical study shows that CT-guided stereotactic biopsy of nonpolar tumors in the dominant hemisphere using the Brown-Roberts-Wells system and the Sedan—Nashold biopsy cannula carries a 9% risk (95% confidence intervals 0–26%) of impairing language functions if the patient is not dysphasic preoperatively. If the patient is dysphasic preoperatively, there is a very high risk of aggravating the dysphasia with stereotactic biopsy.
Basilar invagination in osteogenesis imperfecta and related osteochondrodysplasias: medical and surgical management
Authors: Sawin Paul D. , Menezes Arnold H.
Published: June 2009

✓ Osteogenesis imperfecta (OI) is a heritable disorder of bone development caused by defective collagen synthesis. Basilar invagination is an uncommon but devastating complication of this disease. The authors present a comprehensive strategy for management of craniovertebral anomalies associated with OI and related osteochondrodysplasias.

Twenty-five patients with congenital osteochondrodysplasias (18 OI, four Hajdu—Cheney syndrome, and three spondyloepiphyseal dysplasia) and basilar invagination were evaluated between 1985 and 1995. The male/female ratio in this cohort was 1:1. The mean age at presentation was 11.9 years (range 13 months–20 years). Fourteen patients (56%) presented during adolescence (11–15 years of age). Symptoms and signs included headache (76%), lower cranial nerve dysfunction (68%), hyperreflexia (56%), quadriparesis (48%), ataxia (32%), nystagmus (28%), and scoliosis (20%). Four patients (16%) were asymptomatic. Seven (28%) had undergone previous posterior fossa decompression; one had also undergone ventral decompression. Imaging findings included basilar invagination (100%), ventral brainstem compression (84%), hydrocephalus (32%), hindbrain herniation (28%), and syringomyelia/syringobulbia (16%).

Patients with hydrocephalus underwent ventricular shunt placement. Reducible basilar invagination (40%) was treated with posterior fossa decompression and occipitocervical fusion. Those with irreducible ventral compression (60%) underwent transoral—transpalatopharyngeal decompression followed by occipitocervical fusion. All patients improved initially. However, basilar invagination progressed radiographically in 80% (symptomatic in 24%) despite successful fusion. Prolonged external orthotic immobilization with the modified Minerva brace afforded symptomatic improvement and arrested progression of the deformity. The mean follow-up period was 5.9 years (range 1.1–10.5 years).

Ventral brainstem compression in OI should be treated with ventral decompression, followed by occipitocervical fusion with contoured loop instrumentation to prevent further squamooccipital infolding. Despite fusion, however, basilar invagination tends to progress. Prolonged immobilization (particularly during adolescence) may stabilize symptoms and halt further invagination. This study represents the largest series to date addressing craniovertebral anomalies in OI and related congenital bone softening disorders.
Revision of anterior cervical pseudarthrosis with anterior allograft fusion and plating
Authors: Coric Domagoj , Branch Charles L. , Jenkins Jeffrey D.
Published: June 2009

U Anterior cervical discectomy and fusion is an efficacious procedure used to treat a variety of cervical spinal disorders, including spondylosis, myelopathy, herniated discs, trauma, and degenerative disc disease. Pseudarthrosis, or failure of fusion, may be the most common complication of spinal fusion procedures. Nineteen consecutive patients with symptomatic pseudarthrosis following failed anterior cervical fusions were treated with anterior cervical revision using iliac crest allografts and either the Cervical Spine Locking Plate system (10 patients) or the Trapezial Osteosynthetic Plate system (nine patients). The mean age of the nine men and 10 women undergoing treatment was 49.1 years (range 25–72 years). Eleven patients (57.9%) exhibited pseudarthrosis at one level, six (31.5%) at two levels, and two (10.5%) at three levels. The indications for revision were intractable neck pain with radiculopathy (17 patients) or myelopathy (two patients), with evidence of pseudarthrosis on plain cervical radiography as well as computerized tomography (CT) or single-photon emission computerized tomography (SPECT) scanning, or both. All eight patients evaluated with SPECT showed increased focal uptake consistent with pseudarthrosis, which was subsequently confirmed intraoperatively in all eight. The average follow-up period was 22.4 months (range 12–42 months).

Solid osseous fusion was achieved over all 28 levels in all 18 patients available for follow-up review (100%). One patient died 4 months postoperatively from myocardial infarction related to preexisting coronary artery disease. There were no intraoperative complications; postoperatively, two patients (10.5%) experienced transient hoarseness.

Anterior revision of failed cervical fusions using allograft interbody fusion material and anterior plating is a safe and efficacious procedure. In this series, the use of allografts avoided donor site morbidity without adversely affecting fusion rates. Rigid internal fixation was achieved by means of anterior plating without increasing surgical morbidity rates. The SPECT imaging technique has the potential to reliably confirm the diagnosis of pseudarthrosis.
Reduction of spinal cord injury by administration of iloprost, a stable prostacyclin analog
Authors: Taoka Yuji , Okajima Kenji , Uchiba Mitsuhiro , Murakami Kazunori , Harada Naoaki , Johno Masayoshi , Naruo Masakuni , Okabe Hiroaki , Takatsuki Kiyoshi
Published: June 2009

✓ To investigate whether iloprost, a stable analog of prostacyclin, is useful for the prevention of posttraumatic spinal cord injury, we examined its effects on compression trauma—induced spinal cord injury in rats. Spinal cord injury was induced by applying a 20-g weight for 20 minutes to the spinal cord at the level of T-12, resulting in motor disturbances in the hindlimbs. These motor disturbances, evaluated using Tarlov's index, were markedly attenuated in rats with nitrogen mustard—induced leukocytopenia. Administration of iloprost also attenuated the motor deficits. Histological examination revealed that intramedullary hemorrhages observed 24 hours after trauma were significantly attenuated in leukocytopenic animals and in animals that received iloprost. The accumulation of leukocytes at the site of trauma, evaluated by measuring tissue myeloperoxidase activity, significantly increased with time following the trauma, peaking at 3 hours postinjury. Spinal cord myeloperoxidase activity in sham-operated animals did not increase postoperatively. Leukocyte depletion and administration of iloprost reduced the accumulation of leukocytes in the damaged spinal cord segment 3 hours posttrauma.

These findings indicate that iloprost attenuates motor disturbances induced by spinal cord trauma and that its therapeutic efficacy can be partly explained by its inhibition of leukocyte accumulation at the traumatized site.
Inadequate PAX-1 gene expression as a cause of agenesis of the thoracolumbar spine with failure of segmentation
Authors: Löpez Benjamín C. , Dívid Károly M. , Crockard H. Alan
Published: June 2009

✓ U An unusual case with absence and “fusion” of several thoracic and lumbar vertebral bodies leading to a severe thoracolumbar kyphos is presented. Late-onset neurological deterioration occurred due to spinal cord compression, which was treated with anterior decompression. Although several mechanisms for the development of these extensive and rare abnormalities have been proposed, the cause in humans remains unknown. An embryological basis is presented in the light of recent advances in molecular genetics, which show that abnormal notochordal signals andPax-1gene expression can produce an experimental phenotype very similar to the one in the patient described here. Thus it is suggested that faults in these early developmental processes may be, at least in part, responsible for the development of such extensive anomalies.