Dietary n-3 polyunsaturated fatty acids increase oxidative stress in rats with intracerebral hemorrhagic stroke.

Intake of n-3 polyunsaturated fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) has been suggested to associate with an increased risk of hemorrhagic stroke. The present study was designed to investigate the hypothesis that EPA and DHA increase oxidative stress and hemorrhage volume in rats with intracerebral hemorrhagic (ICH) stroke. Thirty-five-week-old male rats were fed an American Institute of Nutrition-93M diet containing 0% (n = 27), 0.5% (n = 15), or 1% EPA + DHA of total energy for 5 weeks. Of 5 rats fed 1% EPA + DHA (41%), 5 died because of excessive bleeding within 12 hours after ICH surgery. Behavior test score and hemorrhage volume were significantly (P < .05) greater in the 1% EPA + DHA-fed rats than in other rats. Magnetic resonance imaging consistently showed that edema and bleeding were visible in only the rats fed 1% EPA + DHA. Levels of superoxide dismutase and glutathione were significantly (P < .05) lower in rats fed 0.5% and 1% EPA + DHA than those fed 0% EPA + DHA. Thiobarbituric acid-reactive substance content was significantly (P < .05) higher in 1% EPA + DHA-fed rats than in 0% and 0.5% EPA + DHA-fed rats. The level of 8-hydroxydeoxyguanosine was significantly (P < .05) higher in ICH rats with all diets than in sham surgery rats. Brain levels of EPA and DHA were highest in rats fed 1% EPA + DHA than in rats fed 0% and 0.5% EPA + DHA. These results suggested that intake of 1% EPA + DHA of total energy could lead to oxidative damage to the brain and thus increase the risk of intracerebral hemorrhagic stroke in this rat model.

Acute Physiology and Chronic Health Evaluation II and Simplified Acute Physiology Score II in predicting hospital mortality of neurosurgical intensive care unit patients.

We study the predictive power of Acute Physiology and Chronic Health Evaluation II (APACHE II) and Simplified Acute Physiology Score II (SAPS II) in neurosurgical intensive care unit (ICU) patients. Retrospective investigation was conducted on 672 consecutive ICU patients during the last 2 yr. Data were collected during the first 24 hours of admission and analyzed to calculate predicted mortality. Mortality predicted by two systems was compared and, multivariate analyses were then performed for subarachnoid hemorrhage (SAH) and traumatic brain injury (TBI) patients. Observed mortality was 24.8% whereas predicted mortalities were 37.7% and 38.4%, according to APACHE II and SAPS II. Calibration curve was close to the line of perfect prediction. SAPS II was not statistically significant according to a Lemeshow-Hosmer test, but slightly favored by area under the curve (AUC). In SAH patients, SAPS II was an independent predictor for mortality. In TBI patients, both systems had independent prognostic implications. Scoring systems are useful in predicting mortality and measuring performance in neurosurgical ICU setting. TBI patients are more affected by systemic insults than SAH patients, and this discrepancy of predicting mortality in each neurosurgical disease prompts us to develop a more specific scoring system targeted to cerebral dysfunction.

Role of angiogenic growth factors and inflammatory cytokine on recurrence of chronic subdural hematoma.

BACKGROUND: Chronic subdural hematoma, a benign illness with established surgical treatment, occasionally presents as an annoying recurrence. In this paper, we assess the role of local inflammation and angiogenesis on the recurrence of CSH by measuring relevant biochemical factors from surgical specimens. METHODS: During a 2-year period, a prospective comparative study was conducted on 66 consecutive patients with CSH who underwent the same one burr-hole drainage procedure. In the initial operation, the subdural fluid and outer membrane were collected and stored. In the subdural fluid, concentrations of VEGF, bFGF, and IL-6 were measured by the ELISA technique. And semiquantitative analyses were performed with the outer membrane, which was stained by an immunohistochemical method. All data were compared between patients with and without recurrence. RESULTS: The mean concentrations of IL-6, VEGF, and bFGF in subdural fluid in 52 nonrecurrent patients were 1980.2 +/- 229.1, 8262.1 +/- 971.9, and 8.6 +/- 1.4 pg/mL, whereas those in 14 recurrent patients were 2411.3 +/- 446.7, 8646.0 +/- 793.3, and 9.8 +/- 2.6 pg/mL, respectively. Concentration of IL-6 was significantly higher in recurrent patients than in nonrecurrent patients, but no significant differences were found in VEGF and bFGF concentrations. Immunohistochemical staining of the outer membrane showed significantly stronger staining of the VEGF and bFGF in recurrent patients than in those without recurrence, but not of the IL-6. CONCLUSIONS: When patients with CSH exhibit higher concentrations of IL-6 in the subdural fluid, or enhanced expression of VEGF and bFGF in the outer membrane at the initial operation, recurrence is more likely to occur and a precautious follow-up evaluation is mandated. With regard to the recurrence, local inflammation seems to be responsible for continuous bleeding by capillary exudation in the earlier phase, whereas angiogenesis appears to render maturation of the outer membrane by sprouting vascular networks in the later phase.

Neurochemical Characterization of the TRPV1-Positive Nociceptive Primary Afferents Innervating Skeletal Muscles in the Rats.

OBJECTIVE: Transient receptor potential vanilloid subfamily type 1 (TRPV1), a most specific marker of the nociceptive primary afferent, is expressed in peptidergic and non-pepetidergic primary afferents innervating skin and viscera. However, its expression in sensory fibers to skeletal muscle is not well known. In this study, we studied the neurochemical characteristics of TRPV1-positive primary afferents to skeletal muscles. METHODS: Sprague-Dawley rats were injected with total 20 microl of 1% fast blue (FB) into the gastrocnemius and erector spinae muscle and animals were perfused 4 days after injection. FB-positive cells were traced in the L4-L5 (for gastrocnemius muscle) and L2-L4 (for erector spinae muscle) dorsal root ganglia. The neurochemical characteristics of the muscle afferents were studied with multiple immunofluorescence with TRPV1, calcitonin gene-related peptide (CGRP) and P2X(3). To identify spinal neurons responding to noxious stimulus to the skeletal muscle, 10% acetic acids were injected into the gastrocnemius and erector spinae muscles and expression of phospho extracellular signal-regulated kinase (pERK) in spinal cords were identified with immunohistochemical method. RESULTS: TRPV1 was expressed in about 49% of muscle afferents traced from gastrocnemius and 40% of erector spinae. Sixty-five to 60% of TRPV1-positive muscles afferents also expressed CGRP. In contrast, expression of P2X(3) immnoreaction in TRPV1-positive muscle afferents were about 20%. TRPV1-positive primary afferents were contacted with spinal neurons expressing pERK after injection of acetic acid into the muscles. CONCLUSION: It is consequently suggested that nociception from skeletal muscles are mediated by TRPV1-positive primary afferents and majority of them are also peptidergic.

Postoperative changes in paraspinal muscle volume: comparison between paramedian interfascial and midline approaches for lumbar fusion.

In this study, we compared the paramedian interfascial approach (PIA) and the traditional midline approach (MA) for lumbar fusion to determine which approach resulted in the least amount of postoperative back muscle atrophy. We performed unilateral transforaminal posterior lumbar interbody fusion via MA on the symptomatic side and pedicle screw fixation via PIA on the other side in the same patient. We evaluated the damage to the paraspinal muscle after MA and PIA by measuring the preoperative and postoperative paraspinal muscle volume in 26 patients. The preoperative and postoperative cross-sectional area, thickness, and width of the multifidus muscle were measured by computed tomography. The degree of postoperative paraspinal muscle atrophy was significantly greater on the MA side than on the contralateral PIA side (-20.7% and -4.8%, respectively, p<0.01). In conclusion, the PIA for lumbar fusion yielded successful outcomes for the preservation of paraspinal muscle in these 26 patients. We suggest that the success of PIA is due to less manipulation and retraction of the paraspinal muscle and further studies on this technique may help confirm whether less muscle injury has positive effects on the long-term clinical outcome.

Neuroprotective effect of ginseng total saponins in experimental traumatic brain injury.

In the present study, we investigated whether ginseng total saponins (GTSs) protect hippocampal neurons after experimental traumatic brain injury (TBI) in rats. A moderate-grade TBI was made with the aid of a controlled cortical impact (CCI) device set at a velocity of 3.0 m/sec, a deformation of 3.0 mm, and a compression time of 0.2 sec at the right parietal area for adult male Sprague-Dawley rats. Shamoperated rats that underwent craniectomy without impact served as controls. GTSs (100 and 200 mg/kg) or saline was injected intraperitoneally into the rats immediately post-injury. Twenty-four hours after the injury, the rats underwent neurological evaluation. Contusion volume and the number of hippocampal neurons were calculated with apoptosis evaluated by TUNEL staining. 24 hr post-injury, saline-injected rats showed a significant loss of neuronal cells in the CA2 region of the right hippocampus (53.4%, p<0.05) and CA3 (34.6%, p<0.05) compared with contralateral hippocampal region, a significant increase in contusion volume (34+/-8 microL), and significant increase in neurologic deficits compared with the GTSs groups. Treating rats with GTSs seemed to protect the CCI-induced neuronal loss in the hippocampus, decrease cortical contusion volume, and improve neurological deficits.

Common peroneal nerve palsy as a complication of anterior cervical operation: a case report.

BACKGROUND: Common peroneal nerve palsy is a well-recognized complication following orthopedic procedure in and around the knee region. In neurosurgical practice, however, this kind of injury with regard to the patients' position is seldom reported. CASE DESCRIPTION: We describe an immediately developed common peroneal nerve palsy in a 53-year-old slender man who underwent anterior cervical operative procedure. He suffered incomplete common peroneal nerve injury for about 8 months and during this period, he underwent 2 electromyographic examinations suggesting demyelinating injury. He received conservative treatment including physiotherapy and rigid foot orthosis and finally made a favorable but incomplete recovery. CONCLUSION: We propose that such palsy may result from immobilization in a certain position instead of direct compression or traction of the corresponding nerve, although this is not proven. In this report, we suggest the possible risk factors, preventive measures, therapeutic options, and relevant outcome of this unwanted result.