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Vincent C Traynelis

Publications and source records attributed to Vincent C Traynelis.

17 recordsLinked to original sources
PubMed2006

Cis-parinaric acid effects, cytotoxicity, c-Jun N-terminal protein kinase, forkhead transcription factor and Mn-SOD differentially in malignant and normal astrocytes.

Cis-parinaric acid (c-PNA), a natural four conjugated polyunsaturated fatty acid, increases free radical production and it is preferentially cytotoxic to malignant glial cells compared to normal astrocytes in-vitro. In order to explain the increased cytotoxicity of c-PNA in malignant glial cells, we compared the effects of c-PNA on the oxidative stress-dependent signal transducing events in 36B10 cells, a malignant rat astrocytoma cell line, and in fetal rat astrocytes. Our results show that c-PNA treatment in 36B10 cells caused a persistent activation of c-Jun N-terminal protein kinase (JNK) at RNA and protein levels. Specific inhibitors of the kinase significantly reversed the cytotoxicity of c-PNA. Additionally, c-PNA caused the phosphorylated inactivation of forkhead transcription factor-3a (FKHR-L1, FOXO3a) and drastically decreased the activity of mitochondrial superoxide dismutase (Mn-SOD) that protects cells from oxidative stress. On the other hand, identical c-PNA treatments in normal astrocytes increased the dephosphorylated activation of FKHR-L1, maintained activity of Mn-SOD and failed to phosphorylate JNK. Taken together, the results imply that a selective activation of JNK and the opposite regulation of FKHR-L1 and Mn-SOD contribute to the differential cytotoxicity of c-PNA in malignant and normal glial cells.

Animals↗
PubMed2006

Spinal neurenteric cysts in the magnetic resonance imaging era.

OBJECTIVE: Neurenteric cysts are derived from displaced entodermal tissue. They are infrequently found in the ventral spinal canal with varying degrees of success in their removal. Experience with 10 such individuals is critically analyzed to aid in the diagnosis and management. METHODS: Ten patients, ages 4 through 55 years, with neurenteric cysts were encountered in the last 20 years. This series included three females and seven males; seven children and three adults. The follow-up periods ranged from 3 to 18 years. Three cysts were located at the ventral cervicomedullary junction, five in the midventral cervical spine, and one thoracic and one lumbosacral. The symptoms reflected the location. RESULTS: Six of the 10 patients had associated bony abnormalities such as bifid clivus, hemivertebrae, segmentation failures at the site of the lesion, and blocked vertebra. The patient with the thoracic spinal lesion (age, 55 yr) had symptoms from early childhood. A diplomyelia at the site of the lesion was seen in one individual and tethered spinal cord in the same adult and in a young child. Two patients had undergone laminectomy for aspiration and partial resection before referral to our institution at the time of recurrence. Cervicomedullary junction lesions were approached via the far lateral transcondylar approach; two of the cervical intramedullary lesions were resected via a ventral corpectomy with radical resection and interbody fusion. The goal in each case was complete resection to avoid recurrences. CONCLUSION: Spinal neurenteric cysts are ventrally located, usually intradural and extramedullary, but may insinuate into the spinal cord. They are isointense on T1 images and hyperintense on T2-weighted images on magnetic resonance imaging without true enhancement. These lesions may be associated with block and hemivertebrae with a predisposition to the craniocervical region. Partial resections have led to recurrence and arachnoiditis.

Adolescent↗
PubMed2005

Treatment of the painful motion segment: cervical arthroplasty.

STUDY DESIGN: A retrospective review of the literature. OBJECTIVE: This work serves as a comprehensive update of cervical arthroplasty. SUMMARY OF BACKGROUND DATA: Cervical arthroplasty has developed as a means to preserve normal spinal motion after an anterior cervical discectomy. Preserving motion may lead to an acute improvement in patient outcome and may decrease the incidence of symptomatic adjacent segment disease in the long-term. METHODS: The literature concerning the outcomes following anterior cervical decompression and fusion, the indications for cervical arthroplasty, the indications and contraindications for arthroplasty, the surgical technique, and early outcome studies for those devices currently in U.S. FDA IDE trials are reviewed. RESULTS: The most data are available for the Prestige, Bryan, and ProDisc-C devices. While these devices all preserve normal segmental motion, the articulations vary (metal on metal, metal on polyurethane, and metal on ultra-high molecular weight polyethylene). Wear testing indicates that these devices will have a long life once implanted. Preliminary outcomes compare very favorably to anterior decompression and arthrodesis. CONCLUSIONS: Cervical arthroplasty is a promising new technology that may improve patient outcome following anterior cervical decompression.

Arthroplasty↗
PubMed2005

The Prestige cervical disc.

The Prestige LP artificial cervical disc is the most current generation of a disc that has been implanted for well over a decade. This article reviews the history of the device, clinical outcome data, and status of the current US Food and Drug Administration trial. The indications for arthroplasty and the technique for implantation of the Prestige artificial disc are discussed. Anterior reconstruction with the motion sparing Prestige artificial disc is an excellent treatment option for selected patients undergoing anterior cervical decompression.

Arthroplasty, Replacement↗
PubMed2005

Assessment of adjacent-segment disease in patients treated with cervical fusion or arthroplasty: a prospective 2-year study.

OBJECT: The authors compared the incidence of radiologically documented changes and symptomatic adjacent-level cervical disc disease after single-level discectomy and subsequent cervical fusion or arthroplasty in two independent prospective clinical studies. METHODS: The patients were treated with the Affinity Anterior Cervical Cage System or the Bryan Artificial Cervical Disc. In each study the patients were required to undergo serial cervical radiography preoperatively and 24 months postoperatively, as well as serial clinical evaluations including documentation of adverse events, neurological status, and results of the 36-item Short Form Health Survey. All serial radiographs were reviewed prior to evaluating the clinical symptoms for development of increasing or new adjacent degenerative disc disease (DDD). Subsequently, the clinical data were analyzed. For various reasons of exclusion, the cases analyzed in the Bryan disc-treated cohort consisted of 74 patients and in the Affinity system-treated cohort there were 158 patients. New anterior osteophyte formation or enlargement, increased narrowing of an interspace, new DDD, and calcification of the anterior longitudinal ligament were the radiological findings indicative of adjacent-level disease. Fusion was associated with a significant increase in x-ray film-based changes of adjacent-disc disease (p = 0.009, odds ratio [OR] 2.44). In the cage fusion series, the incidence of symptomatic adjacent-level DDD was statistically greater than that in the group treated with the artificial disc (p = 0.018), and the patients required a statistically greater number of medical treatments related to episodic symptoms of neck, shoulder, and arm pain attributed to new disc disease (p = 0.001, OR 35.8). CONCLUSIONS: In comparing these prospective studies the authors demonstrated that maintaining motion rather than fusion will prevent symptomatic adjacent-disc disease and will decrease adjacent-level radiological indicators of disease at a 24-month postoperative interval.

Adult↗
PubMed2004

Case-control study comparing the efficacy of surgical techniques for C1-C2 arthrodesis.

Atlantoaxial fusion rates between 85% and 98% using C1-C2 transarticular screw (TAS) fixation have been reported; however, all of these studies are class III data. As such, these studies carry little or no statistical significance. The authors thus designed a case-control study (class II data) to evaluate the efficacy of C1-C2 TAS fixation as compared with posterior wiring techniques (PWTs). Records of adult subjects were reviewed for fusions isolated to C1-C2. Immobilization requirements were a collar for patients treated with TAS fixation and a halo for those treated by PWT. The minimum acceptable interval of radiographic follow-up was 12 months, and the outcome (fusion or nonunion) was determined through independent interpretation by a radiologist. Twenty-seven of 72 patients undergoing a posterior atlantoaxial arthrodesis met enrollment criteria. Sixteen males and 11 females combined for an average age of 54.1 years and mean follow-up of 31 months. Successful fusions (n = 18) were defined as controls, and cases represented nonunions (n = 9). Successful fusion was achieved in 13 of 14 patients treated with the TAS technique as compared with 5 of 13 subjects who underwent a PWT. Patients with a radiographically solid fusion were 21 more times likely to have undergone TAS than PWT (P = 0.004). This study demonstrated a statistically increased rate of arthrodesis as determined by specific radiographic criteria with the use of TAS fixation as compared with PWT.

Arthrodesis↗
PubMed2004

Clinical course and surgical management of massive cerebral infarction.

OBJECTIVE: Acute occlusion of the proximal middle cerebral artery (MCA) can lead to rapid development of fatal brain swelling and ischemic strokes. Decompressive surgery, if performed early in this subpopulation of patients, can reduce mortality and result in a favorable outcome. In this article, we describe our surgical approach for treating malignant MCA syndrome and compare it with other management strategies. METHODS: This is a retrospective review of patients who developed acute occlusion of the proximal MCA and underwent aggressive surgical decompression (large craniectomy, anterior temporal lobectomy, resection of infarcted tissue, and duraplasty). The outcome of this management strategy is compared with the previously published outcomes of hemicraniectomy and dural augmentation. RESULTS: Twelve patients were included in the study. The group consisted of six men and six women (mean age, 46.8 yr). Nine patients had right MCA stroke, and three had left MCA infarction. The causes of the strokes were cardioembolic, iatrogenic, small-vessel occlusive disease, and others. The interval between infarction and clinical evidence of herniation varied from 24 hours to 10 days. Two patients died, five were independent or had moderate disabilities, and five had severe disability. CONCLUSION: Surgical decompression consisting of a large craniectomy, anterior temporal lobectomy, resection of infarcted tissue, and duraplasty is beneficial to a significant number of patients with massive MCA stroke and clinical signs of herniation.

Adult↗
PubMed2003

The effect of wearing a restrictive neck brace on driver performance.

OBJECTIVE: Thousands of Americans are prescribed cervical orthoses each year. These orthoses restrict motion, which may influence the patient's driving performance. No legal restrictions exist that prohibit patients from wearing cervical orthoses while driving. No study addressing this issue has been published to date. Thus, we sought to assess the effects of wearing a restrictive neck brace on driver performance on the open road. METHODS: We conducted a prospective, randomized block design study in 23 volunteers. Twenty-three adult licensed drivers from the state of Iowa were recruited. Evaluation of neck motion was performed with and without the rigid cervical orthosis. On-road performance testing was conducted with the use of a state-of-the-art mobile laboratory. Drivers were randomly assigned to one of two testing groups. Each driver was evaluated during two separate drives. Volunteers in Group A (n = 11) wore a neck brace for the first drive but not during the second. Participants in Group B (n = 12) did not wear a neck brace in the first drive but did for the second. The assessment included velocity, acceleration, cervical axial rotation, and evaluation of the driver's blind spot. RESULTS: Driving performance measures were collected and analyzed for both drives. Wearing a cervical orthosis resulted in decreased velocity (P < 0.05), decreased lateral acceleration (P < 0.05), decreased axial rotation (P < 0.05), inadequate evaluation of intersection traffic, and an increase in the blind spot. CONCLUSION: A rigid cervical orthosis alters driver performance.

Adult↗
PubMed2002

Spinal arthroplasty.

Symptomatic degenerative spinal disease is a serious medical condition that affects many individuals. Modern neuroimaging modalities, the development of new medications, and advances in operative and nonoperative treatments have all contributed to improved outcomes. Unfortunately, there remain a significant number of patients in whom primary therapy either fails or new or recurrent symptoms develop over time. The last decade has witnessed the invention of devices designed to reconstruct the spinal motion segment. These devices can be divided into those that primarily function to replace a nucleus pulposus and those that completely replace the disc complex. In this article the author reviews the background leading to the development of the current group of disc replacements. The design and preliminary clinical results obtained using major lumbar and cervical devices are also reviewed.

Arthroplasty, Replacement↗
PubMed2002

Posterior cervical fixation using a new polyaxial screw and rod system: technique and surgical results.

OBJECT: Standard lateral mass plate and screw systems are of limited use in patients with abnormal cervical anatomy and do not easily allow for extension to either the occipit or the thoracic spine. The objective of this study was to demonstrate the safety, surgical efficacy, and advantages of a new cervical polyaxial screw and rod system for posterior occipitocervicothoracic arthrodesis. METHODS: The authors reviewed a multicenter series of patients who underwent surgery in which they used a new posterior cervical polyaxial screw and rod system. The system was implanted in 32 (20 women and 12 men) adult patients (mean age 56.9 years, range 23-84 years). Twenty-three of the patients were treated for spondylostenosis; four for cervical fracture/dislocations; four for kyphosis; and one patient was treated for pseudarthrosis that developed after prior surgery. The system was successfully implanted in all patients despite the presence of anatomical lateral mass anomalies in the majority of cases. The mean number of levels fused was 3.9 (range one-eight levels). This dynamic system allowed for screw placement into the occiput, C-1 lateral masses, C-2 pars, C3-7 lateral masses, and low cervical as well as upper thoracic pedicles. Selective application of compressive or distractive forces was possible in adjacent segments. Surgery-related complications included one dural tear and one malpositioned screw. There were two cases of wound infection. CONCLUSIONS: Unlike standard lateral mass plate and screw systems, the new cervical polyaxial screw and rod system easily accommodates severe degenerative cervical spondylosis and curvatures. This instrumentation system allows for polyaxial screw placement with subsequent multiplanar rod contouring and offset attachment. The authors have used this system successfully, and without significant complications, to achieve posterior cervical arthrodesis.

Adult↗
PubMed2002

Free tissue transfer and local flap complications in anterior and anterolateral skull base surgery.

BACKGROUND: Advances in reconstructive techniques over the past two decades have allowed the resection of more extensive skull base tumors than had previously been possible. Despite this progress, complications related to these cases remain a concern. METHODS: Univariate and multivariate analyses were used to determine the relationship of host, tumor, defect, treatment, and reconstructive variables to wound and systemic complications after anterior and anterolateral skull base resections. The study included 67 patients receiving local flap (LF) or free tissue transfer (FTT) reconstructions during an 8-year period. RESULTS: Overall, 28% of patients had a major wound complication, and 19% had a major systemic complication. LF and FTT flaps had similar rates of wound complications. LF reconstructions were associated with late wound breakdown problems, and FTT flap complications were primarily acute surgery-related problems. CONCLUSIONS: The surgical reconstruction of skull base defects should be planned on the basis of the ability of the technique to attain safe closure and maintain integrity after radiation therapy.

Adolescent↗
PubMed2002

Treatment of delayed-onset neurological deficit after aortic surgery with lumbar cerebrospinal fluid drainage.

OBJECTIVE: The phenomenon of delayed neurological deficit after thoracoabdominal aortic aneurysm repair was first reported in the late 1980s. The mechanism may be reduced collateral circulation during periods of hypotension, cord edema, or reperfusion injury. Few patients with delayed-onset neurological deficit have recovered from this devastating complication. The experience with six patients treated with lumbar cerebrospinal fluid (CSF) drainage is reported. METHODS: Five patients underwent thoracoabdominal aortic aneurysm repair. Before and immediately after the operation, the patients exhibited no abnormalities in motor or sensory function. Patients presented between 12 and 40 hours postoperatively with rapid motor and sensory loss in their lower extremities. Hypotensive events immediately preceded the onset of deficit in five patients. The sixth patient experienced an acute onset of back pain and was found to have thrombus without evidence of dissection in the descending aorta. RESULTS: Patients were treated with volume expansion and vasoactive drugs to achieve a mean arterial pressure of more than 70 mm Hg. Lumbar CSF drainage was instituted promptly in four patients; all displayed marked neurological improvement. Two patients underwent CSF drainage several hours after the onset of symptoms and did not improve. The duration of CSF drainage ranged from 15 to 72 hours, with a goal of maintaining the lumbar CSF pressure at less than 10 mm Hg. CONCLUSION: The efficacy of CSF drainage may relate to reducing CSF pressure, which may increase spinal cord perfusion. Rapid initiation of CSF drainage with aggressive support of blood pressure may result in neurological improvement in some patients.

Aged↗
PubMedDate not supplied

The Prestige cervical disc replacement.

BACKGROUND CONTEXT: Anterior cervical discectomy and arthrodesis is the preferred treatment for a large number of patients with symptomatic cervical spondylosis. This management strategy is successful for the majority of patients, and the short-term results are very good. There is the potential to further improve patient outcome and the long-term success rate. PURPOSE: The purpose of this report is to review the rationale for cervical arthroplasty and describe the development of the Prestige cervical disc replacement (Medtronic Sofamor Danek, Inc., Memphis, TN). STUDY DESIGN/SETTING: This report reviews the literature concerning the need for cervical arthroplasty and details the basic and clinical work on the Prestige cervical disc replacement. METHODS: The key publications concerning the shortcomings of cervical arthrodesis and the clinical and basic studies on the Prestige cervical disc implant are discussed. New long-term clinical data on the Prestige device are reported. RESULTS: Cervical arthrodesis perturbs normal cervical spinal biomechanics and appears to be associated with accelerated degeneration of the adjacent segments. The Prestige cervical disc replacement is successful in preserving normal spinal motion, both experimentally and clinically. The device is durable, and the clinical outcomes have been excellent. CONCLUSIONS: The Prestige cervical disc replacement is an effective means of reconstructing the cervical spine after anterior discectomy. It preserves normal motion and may decrease the incidence of adjacent segment disease.

Arthroplasty, Replacement↗