Acute histopathological responses and long-term behavioral outcomes in mice with graded controlled cortical impact injury.

While animal models of controlled cortical impact often display short-term motor dysfunction after injury, histological examinations do not show severe cortical damage. Thus, this model requires further improvement. Mice were subjected to injury at three severities using a Pin-Point™-controlled cortical impact device to establish secondary brain injury mouse models. Twenty-four hours after injury, hematoxylin-eosin staining, Fluoro-Jade B histofluorescence, and immunohistochemistry were performed for brain slices. Compared to the uninjured side, we observed differences of histopathological findings, neuronal degeneration, and glial cell number in the CA2 and CA3 regions of the hippocampus on the injured side. The Morris water maze task and beam-walking test verified long-term (14-28 days) spatial learning/memory and motor balance. To conclude, the histopathological responses were positively correlated with the degree of damage, as were the long-term behavioral manifestations after controlled cortical impact. All animal procedures were approved by the Institutional Animal Care and Use Committee at Shanghai Jiao Tong University School of Medicine.

Improved neurite outgrowth on central nervous system myelin substrate by siRNA-mediated knockdown of Nogo receptor.

PURPOSE: To investigate the in vitro effect of short interfering RNAs (siRNAs) against Nogo receptor (NgR) on neurite outgrowth under an inhibitory substrate of central nervous system (CNS) myelin. METHODS: Three siRNA sequences against NgR were designed and transfected into cerebellar granule cells (CGCs) to screen for the most effcient sequence of NgR siRNA by using reverse transcription polymerase chain reaction (RT-PCR) and immunofluorescence staining. NgR siRNA sequence 1 was found the most efficient which was then transfected into the CGCs grown on CNS myelin substrate to observe its disinhibition for neurite outgrowth. RESULTS: Compared with the scrambled control sequence of siRNA, the NgR siRNA sequence 1 significantly decreased NgR mRNA level at 24 h and 48 h (p <0.05), which was recovered by 96 h after transfection. NgR immunoreactivity was also markedly reduced at 24 and 48 h after the transfection of siRNA sequence 1 compared with that before transfection (p<0.05). The NgR immunoreactivity was recovered after 72 h post-transfection. Moreover, the neurite outgrowth on the myelin substrate was greatly improved within 72 h after the transfection with siRNA sequence 1 compared with the scrambled sequence-transfected group or non-transfected group (p<0.05). CONCLUSION: siRNA-mediated knockdown of NgR expression contributes to neurite outgrowth in vitro.

The up-regulation of voltage-gated sodium channel Nav1.6 expression following fluid percussion traumatic brain injury in rats.

BACKGROUND: The influx of Na and the depolarization mediated by voltage-gated sodium channels (VGSCs) is an early event in traumatic brain injury (TBI) induced cellular abnormalities and is therefore well positioned as an upstream target for pharmacologic modulation of the pathological responses to TBI. Alteration in the expression of the VGSC alpha-subunit has occurred in a variety of neuropathological states including focal cerebral ischemia, spinal injury, and epilepsy. OBJECTIVE: In this study, changes in Nav1.6 mRNA and protein expression were investigated in rat hippocampus after TBI. METHODS: Forty-eight adult male Sprague Dawley rats were randomly assigned to control or TBI groups. TBI was induced with a lateral fluid percussion device. Expression of mRNA and protein for Nav1.6 in the bilateral hippocampus was examined at 2, 12, 24, and 72 hours after injury by real-time quantitative polymerase chain reaction and Western blot. Immunofluorescence was performed to localize the expression of Nav1.6 protein in the hippocampus. RESULTS: Expression of >Nav1.6 mRNA was significantly up-regulated in the bilateral hippocampus at 2 and 12 hours post-TBI. Significant up-regulation of Nav1.6 protein was identified in the ipsilateral hippocampus from 2 to 72 hours post-TBI and in the contralateral hippocampus from 2 to 24 hours post-TBI. Expression of Nav1.6 occurred predominantly in neurons in the hippocampus. CONCLUSION: Results of the study showed significant up-regulation of mRNA and protein for Nav1.6 in rat hippocampal neurons after TBI.

Bilateral decompressive craniectomy for patients with malignant diffuse brain swelling after severe traumatic brain injury: a 37-case study.

Abstract In this study we retrospectively analyzed the outcome of bilateral decompressive craniectomy (BDC) for 37 patients with bilateral malignant diffuse brain swelling following severe traumatic brain injury (TBI). Our 37 patients (Glasgow Coma Scale [GCS] score 6 months of follow-up. The mean ICP was 37.7 +/- 6.4 mm Hg, and the mean CPP was 57.6 +/- 7.5 mm Hg before BDC. The ICP significantly decreased to 27.4 +/- 7.2 mm Hg (p < 0.05) after bone removal, and the CPP significantly increased to 63.3 +/- 8.4 mm Hg (p < 0.05). The ICP had a larger decrease, to 11.2 +/- 7.1 mm Hg (p < 0.05), after opening and enlargement of the dura mater (p < 0.05) compared to the levels seen after bone removal, and CPP significantly increased to 77.8 +/- 8.3 mm Hg (p < 0.05). After surgery, the ICP was elevated, but remained lower than the initial ICP (p < 0.05), and was easily controlled by routine medical treatment in the ensuing days, and the CPP remained above the optimal threshold of 70 mm Hg. The mean follow-up time was 9.4 +/- 3.2 months. In total, 20 patients (54.1%) had favorable outcomes, including 12 patients (32.5%; GOS 4) with moderate deficits, and 8 patients (21.6%; GOS 5) showed good recovery and social reintegration. Also, 17 patients (45.9%) had unfavorable outcomes, including 7 patients (18.9%; GOS 1) who died, 4 patients (10.8%; GOS 2) remained in a vegetative state, and 6 patients (16.2%; GOS 3) had severe deficits. The most common complication was hydrocephalus (7 patients, 18.9%). Our data show that BDC offers immediate reductions in intracranial hypertension, and perhaps contributes to satisfactory outcomes in patients with bilateral diffuse brain swelling following severe TBI.

Effects of dose-response of topical administration of nimodipine on cerebral vasospasm after subarachnoid hemorrhage in rabbits.

BACKGROUND: To explore the dose-response effects of topical administration of nimodipine on cerebral vasospasm (CVS) after subarachnoid hemorrhage (SAH) in rabbits. METHODS: The CVS model was established by injection of fresh autologous nonheparinized arterial blood into the subtemporal area of basilar cisterns. The 24 CVS animals were randomly divided into 4 groups, group I (n=7): nimodipine original stock solution/normal saline=1/19 (0.01 mg/mL); group II (n=6): nimodipine original stock solution/normal saline=1/9 (0.02 mg/mL); group III (n=5): nimodipine original stock solution/normal saline=1/4 (0.04 mg/mL); and group IV (n=6) with no nimodipine, but 5% ethanol dissolved in normal saline as the control group. The operative area was administrated with nimodipine at different concentrations or alcohol-saline at 3 days after SAH. The blood flow velocity of middle cerebral artery was measured at 5, 15, 30, and 60 minutes after topical administration of nimodipine by transverse cerebellar diameter monitoring. RESULTS: Blood flow velocity of middle cerebral artery in group II (0.02 mg/mL) and in group III (0.04 mg/mL) significantly decreased at 60 and 15 minutes, respectively, after topical administration of nimodipine (P<0.05), and even more significantly at 30 and 60 minutes after topical administration of nimodipine in group III (0.04 mg/mL) (P<0.01). CONCLUSION: Topical administration of nimodipine at the concentrations of 1:5 (0.04 mg/mL) and 1:10 (0.02 mg/mL) significantly alleviates CVS after SAH, which indicates that topical administration of nimodipine may be useful for CVS of patients with SAH during surgical clip of intracranial aneurysms.

Surgical management of anterior clinoidal meningiomas: a 26-case report.

BACKGROUND: Resection of anterior clinoidal meningiomas remains a major neurosurgical challenge. We determine the surgical technique for removal of tumor and improvement of patient's outcome. METHODS: A retrospective analysis was performed on 26 consecutive patients with anterior clinoidal meningiomas who underwent surgical resection at the Department of Neurosurgery, Renji Hospital, from January 1999 to August 2006. All patients had surgery through the pterional or extended pterional approach. Microvascular Doppler probe was used to protect the internal carotid artery and its branching arteries during dissection of the tumor. Twenty-two of them had severe visual deficits preoperatively. The follow-up period ranged from 3 to 36 months (22.3 +/- 8.8 months). RESULTS: In this series, Simpson grade II resection in 16 cases (61.5%), Simpson grade III resection in 4 cases (15.4%), Simpson grade IV resection in 6 cases (23.1%) were achieved. Sixteen of the patients with preoperative visual impairment experienced significant improvement. No patients died. There was no evidence of tumor recurrence during follow-up. CONCLUSIONS: In the majority of patients, surgery is still the first choice for total resection of the tumors without major complications. Protection of nerves and blood vessels must be a priority concern during removal of tumors.

Effect of long-term mild hypothermia or short-term mild hypothermia on outcome of patients with severe traumatic brain injury.

To compare the effect of long-term mild hypothermia versus short-term mild hypothermia on the outcome of 215 severe traumatic brain injured patients with cerebral contusion and intracranial hypertension. At three medical centers, 215 patients aged 18 to 45 years old with an admission Glasgow Coma Scale < or =8 within 4 h after injury were randomly divided into two groups: long-term mild hypothermia group (n = 108) for 5+/-1.3 days mild hypothermia therapy and short-term mild hypothermia group (n = 107) for 2+/-0.6 days mild hypothermia therapy. All patients had intracranial hypertension and frontotemporoparietal contusion with midline shift >1 cm confirmed on computed tomographic scan. Glasgow Outcome Scale at 6-month follow-up, 47 cases had favorable outcome (43.5%), and other 61 cases had unfavorable outcome (56.5%) in the long-term mild hypothermia group. However, only 31 cases had favorable outcome (29.0%), and other 76 cases had unfavorable outcome (71.0%) in the short-term mild hypothermia group (P < 0.05). The intracranial pressure significantly rebounded after rewarming in the short-term mild hypothermia group, but not in the long-term mild hypothermia (P < 0.05). Furthermore, the incidence of stress ulcer, epilepsy, pulmonary infection, intracranial infection did not significantly differ between the two groups (P > 0.05). Compared with short-term mild hypothermia, long-term mild hypothermia significantly improves the outcome of severe traumatic brain injured patients with cerebral contusion and intracranial hypertension without significant complications. Our data suggest that 5 days of long-term cooling is more efficacious than 2 days of short-term cooling when mild hypothermia is used to control refractory intracranial hypertension in patients with severe traumatic brain injury.

[Influence of elemene on the expression of Bcl-2 family genes in rat C6 glioma cells].

OBJECTIVE: To observe the effects of elemene on the induction of apoptosis in rat C6 glioma cells and its influence on expression of Bcl-2 family genes. METHODS: Rat C6 glioma cells were cultured. Elemene of the concentrations of 0, 20, 40, 60, and 80 microg/ml were added for 12, 24, 36, 48, and 72 hours respectively. RT-PCR was used to detect the mRNA expression of Bcl-2/Bcl-x/1 genes. Western blotting was used to detect the protein expression of Bcl-2/Bcl-x/1 genes. The apoptosis of the cells was examined by flow cytometry. RESULTS: The cell counts of the 20, 40, 60, and 80 microg/ml elemene groups were 536 +/- 9, 375 +/- 10, 246 +/- 9, and 112 +/- 10/visual field respectively, all significantly lower than that of the 0 microg/ml elemene group (all F = 1292.416, P < 0.05) and the apoptotic rates of the 20, 40, 60, and 80 microg/ml elemene groups were (27 +/- 2)%, (29 +/- 4)%, (32 +/- 3)%, and (35 +/- 5)% respectively with an Ap peak. The protein expression of Bcl-2/Bcl-x/l genes was decreased in the elemene groups dose and time-dependently. The expression of Bax protein was decreased in the elemene groups too, however, not dose and time-dependently. CONCLUSION: Apoptosis caused by elemene may be associated with the down-regulation of Bcl-2/Bcl-x/l genes.

Loss of heterozygosity on chromosome 22 in sporadic schwannoma and its relation to the proliferation of tumor cells.

BACKGROUND: Schwannoma is the tumor arising mainly from the cranial and spinal nerves. Bilateral vestibular schwannoma is the hallmark of neurofibromatosis type 2 (NF2). The NF2 gene has been cloned with comprehensive analysis of its mutations in schwannoma. However, most studies focused on vestibular schwannoma. There are differences in proliferation of tumor cell and ultrastructure between vestibular and spinal schwannomas. It is unknown whether genetic alterations in vestibular schwannoma are different from those in non-vestibular schwannoma. We analyzed the loss of heterozygosity (LOH) on chromosome 22 in patients with sporadic schwannoma including vestibular and spinal schwannomas and correlated this genetic alteration with tumor proliferation. METHODS: In 54 unrelated patients without clinical NF1 or NF2, 36 patients had sporadic vestibular schwannoma, and 18 dorsal spinal root schwannoma. Four highly polymorphic linkage to NF2 gene microsatellite DNA markers (D22S264, D22S268, D22S280, CRYB2) were used to analyze LOH. The proliferative index was evaluated by Ki-67 and proliferative cell nuclear antigen (PCNA) immunostaining. Student's t test was used to analyze the difference of the proliferative index between schwannoma with LOH and that without LOH. The difference of the frequency of LOH in vestibular and spinal schwannomas was investigated by the chi-square test. RESULTS: Twenty-three schwannomas (42.6%, 23/54) showed allele loss. The frequency of LOH in vestibular schwannoma was significantly higher than that in spinal schwannoma (chi2 = 5.14, P < 0.05). The proliferative index of schwannoma with LOH was significantly higher than that without LOH (tki-67 = 2.97, P = 0.0045; tPCNA = 2.93, P = 0.0051). CONCLUSIONS: LOH on chromosome 22 is a frequent event in the tumorigenesis of sporadic schwannoma. And, there is a correlation between LOH on chromosome 22 and proliferative activity in schwannoma. The frequency of LOH in vestibular schwannoma is significantly different from that in spinal schwannoma.

Molecular genetics alterations and tumor behavior of sporadic vestibular schwannoma from the People's Republic of China.

OBJECTIVES: To analyze the molecular genetic alteration of sporadic vestibular schwannomas from the People's Republic of China and to correlate these alterations with the tumor behaviors. METHODS: Four highly polymorphic microsatellite DNA markers were used to observe the frequency of loss of heterozygosity (LOH) in chromosome 22. The NF2 gene mutations were detected by Polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and DNA sequencing. The schwannomin/merlin (S/M) expression was examined using anti-NF2 (A-19) IgG under immunohistochemistry and western blot. The proliferative index (LI) of vestibular schwannoma was evaluated by proliferative cell nuclear antigen investigation. RESULTS: Sixteen vestibular schwannomas (44.4%) showed allele loss. We found 22 mutations in 36 schwannomas. The LI and the growth rate of schwannomas with LOH or mutation were significantly higher than those without LOH or mutation. All of these vestibular schwannomas showed no immunoreaction to anti-NF2(A-19) IgG by immunohistochemistry. By immunoblotting technique, reduced expression of S/M was found in 31 cases (86%). The growth index of schwannomas with severely reduced expression of S/M was significantly higher than those with moderately reduced or normal expression. CONCLUSION: The molecular genetic changes in sporadic vestibular schwannomas from Chinese patients were similar to the previous reports. We demonstrate the relationship between tumor behaviors and genetic alteration (including LOH and mutation of NF2 gene). We propose that inactivation of S/M, may be an important step in tumorigenesis of sporadic vestibular schwannoma.

Efficacy of standard trauma craniectomy for refractory intracranial hypertension with severe traumatic brain injury: a multicenter, prospective, randomized controlled study.

To compare the effect of standard trauma craniectomy (STC) versus limited craniectomy (LC) on the outcome of severe traumatic brain injury (TBI) with refractory intracranial hypertension, we conducted a study at five medical centers of 486 patients with severe TBI (Glasgow Coma Scale score 0.05). The results of the study indicate that STC significantly improves outcome in severe TBI with refractory intracranial hypertension resulting from unilateral frontotemporoparietal contusion with or without intracerebral or subdural hematoma. This suggests that STC, rather than LC, be recommended for such patients.

Effect of arousal methods for 175 cases of prolonged coma after severe traumatic brain injury and its related factors.

OBJECTIVE: To determine the effect of arousal methods for prolonged coma of 175 patients with severe traumatic brain injury and related factors. METHODS: There were 175 cases with persistent coma longer than 1 month after severe traumatic brain injury. Coma lasted 1-12 months. Arousal procedures included hyperbaric oxygen, physical therapy and arousal drugs. RESULTS: In the 175 prolonged coma patients 110 got recovery of consciousness; in 118 cases with coma of 1-3 months, 86 cases recovered consciousness (72.9%); in 42 cases with coma of 4-6 months, 20 cases recovered consciousness (47.6); and in 15 cases with coma of longer than 6 months, only 4 cases recovered consciousness (26.7%). The recovery of consciousness depended on patient's primary brain stem damage, cerebral hernia, GCS score, and age. CONCLUSIONS: Application of appropriate arousal procedures improves recovery of consciousness in patients with prolonged coma.

Effect of mild hypothermia on brain dialysate lactate after fluid percussion brain injury in rodents.

OBJECTIVE: To investigate the effects of mild hypothermia on brain microdialysate lactate after fluid percussion traumatic brain injury (TBI) in rats. METHODS: Brain dialysate lactate before and after fluid percussion brain injury (2.1 +/- 0.2 atm) was measured in rats with preinjury mild hypothermia (32 degrees C), postinjury mild hypothermia (32 degrees C), injury normothermia (37 degrees C), and the sham control group. Mild hypothermia (32 degrees C) was induced by partial immersion in a water bath (0 degrees C) under general anesthesia and maintained for 2 hours. RESULTS: In the normothermia TBI group, brain extracellular fluid lactate increased from 0.311 +/- 0.03 to 1.275 +/- 0.08 mmol/L within 30 minutes after TBI (P < 0.01) and remained at a high level (0.546 +/- 0.05 mmol/L) (P < 0.01) at 2 hours after injury. In the postinjury mild hypothermic group, brain extracellular fluid lactate increased from 0.303 +/- 0.03 to 0.875 +/- 0.05 mmol/L at 15 minutes after TBI (P < 0.01) and then gradually decreased to 0.316 +/- 0.04 mmol/L at 2 hours after TBI (P > 0.05). In the preinjury mild hypothermic group, brain extracellular fluid lactate remained at normal levels after injury (P > 0.05). CONCLUSION: The cerebral extracellular fluid lactate level increases significantly after fluid percussion brain injury. Preinjury mild hypothermia completely inhibits the cerebral lactate accumulation, and early postinjury mild hypothermia significantly blunts the increase of cerebral lactate level after fluid percussion injury.

[Experimental study on apoptosis induced by elemene in glioma cells].

BACKGROUND & OBJECTIVE: Elemene, isolated from the Chinese medicinal herb Rhizoma Zedoariae, was shown to exhibit antitumor activity. Our previous studies showed that elemene had a markedly antineoplastic activity on glioma. This study was designed to investigate the proliferation inhibitory effect and the apoptosis-inducing activity of elemene on glioma cells. METHODS: The effects of elemene on cell proliferation were studied in vitro by using (3)H-TdR incorporation. The morphological alterations were confirmed by Hoechst 33258/PI staining. The apoptosis was evaluated by flow cytometry analysis and agarose gel electrophoresis. RESULTS: Elemene exhibited a marked antiproliferative effect on rat glioma cell C6 and human glioma cell SHG-44. The fifty percent inhibition concentration (IC(50)) of elemene against glioma cell lines at different time points (D1-D4) by (3)H-TdR incorporation was C6 7.33-11.02 mg/L, SHG-44 13.29-27.16 mg/L. At the same concentration, human glioma cell line SHG-44 was found to be less sensitive to elemene compared to rodent cell line C6. The characteristic nucleolus alternations under fluorescent microscope included condensation of chromatin arranged under the nuclear membrane and apoptotic bodies, with a low nuclear/cytoplasmic ratio. In flow cytometry analysis, a typical subdiploid peak before Phase G(0)/G(1) (apoptotic peak) was detected in DNA frequency distribution histograms. Also the apoptosis in glioma cells was confirmed by DNA ladder formation on gel electrophoresis. CONCLUSION: Elemene exhibited a marked antiproliferative effect on glioma cells, and it could induce apoptosis in vitro.