Chinese Internet Searches Provide Inaccurate and Misleading Information to Epilepsy Patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Most patients with epilepsy want to learn as much as possible about the disease, and many have turned to the internet for information. Patients are likely to use information obtained from the internet to control their epilepsy, but little is known about the accuracy of this information. In this survey, we have assessed the feasibility and usability of internet-based interventions for the treatment of epilepsy.</p><p><b>METHODS</b>Data were collected from an internet search. Different search terms were used to obtain general information on epilepsy together with information about medication, types of epilepsy, treatment, women's health, and other information. The accuracy of the information was evaluated by a group of experts.</p><p><b>RESULTS</b>A total of 1320 web pages were assessed. The majority were websites related to health. A large number (80.2%) of web pages contained content related to the search term. A significant number of web pages 450/1058 (42.5%) claimed to provide information from a credible source; however, only 206/1058 (19.5%) of the information was accurate and complete; 326/1058 (30.8%) was accurate but incomplete; 328/1058 (31.0%) was correct but nonstandard, and 198/1058 (18.8%) was inaccurate. The authenticity of the information was not significantly different between the two search engines (χ2 = 0.009, P = 0.924). No significant difference was observed in the information obtained from a specialist or nonspecialist source (χ2 = 7.538, P = 0.057). There was also no correlation between the quality of the information and the priority (χ2 = 6.880, P = 0.076).</p><p><b>CONCLUSIONS</b>Searching for information about epilepsy on the internet is convenient, but the information provided is not reliable. Too much information is inaccurate or for advertisement purposes, and it is difficult for patients to find the useful information. Turning to the internet for medical knowledge may be harmful. Physicians should be aware that their patients may search for information on the internet and guide them to safe, reputable websites.</p>

Biocompatibility of a novel cavernous nickel-titanium alloy with rat bone marrow stromal cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the biocompatibility of a novel cavernous nickel-titanium alloy with rat bone marrow stromal cells (BMSCs) in vitro.</p><p><b>METHODS</b>Rat BMSCs were cultured on the surface of compact, microporous and macroporous nickel-titanium alloys, and the cell proliferation on day 3 during the culture was assessed using MTT assay. On day 7 of the cell culture, the cells were labeled with Hoechst33342 for cell counting under a fluorescence microscope. Scanning electron microscopy (SEM) was performed on day 7 of cell culture to observe the morphological changes of the cells.</p><p><b>RESULTS</b>The cell proliferation rate and cell numbers differed significantly between the cavernous alloy groups and the compact alloy group (P<0.05), but similar between the former two groups (P>0.05). SEM showed that compared with the compact alloy, microporous and macroporous nickel-titanium alloys had better biocompatibility with the BMSCs, and the cells on the surface of the cavernous alloys had normal cell morphology.</p><p><b>CONCLUSION</b>Cavernous nickel-titanium alloy has good biocompatibility and can promote the adhesion, aggregation and proliferation of rat BMSCs in vitro.</p>

Evaluation of peritumoral brain edema in intracranial meningiomas using CT perfusion imaging / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the perfusion characteristics of the peritumoral brain edema of intracranial meningiomas using 16-slice spiral CT perfusion imaging.</p><p><b>METHODS</b>Dynamic contrast-enhanced single-location sequence CT scan was performed in 19 patients with intracranial meningiomas and peritumoral brain edema. The regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV) and the mean transit time (MTT) were calculated for the peritumoral brain edema and the contralateral white matter and comparatively analyzed.</p><p><b>RESULTS</b>The rCBF and rCBV in the peritumoral brain edema were significantly lower than those of the contralateral white matter in patients with meningiomas (rCBF: 14.26-/+7.44 vs 26.92-/+15.71 ml/100 g tissue.min, P<0.05; rCBV: 0.96-/+0.35 vs 2.47-/+1.69 ml/100 g tissue, P<0.05). But the MTT showed no significant difference between the peritumoral brain edema and the contralateral white matter (P>0.05).</p><p><b>CONCLUSION</b>The rCBF and rCBV are significantly lowered in the peritumoral brain edema in comparison with those of the contralateral white matter. Vascular compression by the edema fluid may have a major effect on the tissue blood flow and blood volume.</p>

Culture and identification of neural stem cells derived from the subventricular zone of adult mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a method for culturing and identifying neural stem cells (NSCs) derived from the subventricular zone (SVZ) in adult mice.</p><p><b>METHODS</b>NSCs were isolated from the SVZ of adult mouse brain and cultured in serum-free medium. Cell cloning and BrdU incorporation were performed to identify the self-renewal and proliferative capacity of the NSCs. Fluorescence immunocytochemistry was used to examine the expressions of the NSC markers nestin and SOX2, neuronal marker Tuj1, astrocyte marker GFAP and oligodendrocyte marker NG2. The expressions of nestin and SOX2 were further examined by Western blotting and RT-PCR.</p><p><b>RESULTS</b>NSCs with self-renewal and proliferative capacity were obtained from the SVZ of adult mice and grown as floating neurospheres. The NSCs expressed nestin and SOX2 and could differentiated into Tuj1-positive neurons, GFAP-positive astrocytes and NG2-positive oligodendrocytes.</p><p><b>CONCLUSION</b>This method allows simple and stable culture of NSCs from the SVZ of adult mice.</p>

Application of virtual imaging technique in diagnosis of intracranial aneurysms / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the value of virtual imaging technique in diagnosis of intracranial aneurysms.</p><p><b>METHODS</b>Fifty-four cases of 54 intracranial aneurysm diagnosed by three-dimensional CT angiography (3D-CTA) examinations were enrolled in this study. Three-dimensional virtual images of the skull and cerebral vessels were acquired by three-dimensional reconstruction of the original CT images using the surgical planning system, and the location, size and shape of the aneurysms and their anatomical relationship with the adjacent tissues were observed and measured from several angles. All the patients underwent surgical planning and simulated surgical operations using the virtual surgical instruments available in the system.</p><p><b>RESULTS</b>All the 54 cases had successful three-dimensional virtual image reconstruction and the surgical planning operations. The virtual imaging system generated clear and vivid three-dimensional virtual images which clearly visualized the location and size of the aneurysms and their precise anatomical relations to the parent arteries and skull. This virtual reality imaging system also allowed simulation of simple surgical procedures.</p><p><b>CONCLUSION</b>The surgical planning system based on the virtual reality imaging can serve as a useful means to assist the diagnosis and provide precise imaging details of intracranial aneurysms.</p>

Combined application of virtual imaging techniques and three-dimensional computed tomographic angiography in diagnosing intracranial aneurysms / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The diagnostic value of virtual imaging combined with three-dimensional computed tomographic angiography (3D-CTA) for intracranial aneurysms has not been fully elucidated yet. This study aimed to evaluate the value of combined application of virtual imaging techniques and 3D-CTA in diagnosing patients with aneurismal subarachnoid hemorrhage (SAH) at the acute stage.</p><p><b>METHODS</b>Eighty patients with non-traumatic SAH received 3D-CTA examinations. The raw CT data of these patients were reconstructed and transferred into the 3D mode through the surgical plan system based on virtual reality (VR) image, and the 3D virtual images of skulls and brain blood vessels were acquired. The location, size and shape of aneurysms and their anatomic relationship with adjacent tissues were measured from many points of view.</p><p><b>RESULTS</b>Seventy-three aneurysms were detected in 68 of the 80 patients, but 2 aneurysms were detected in 2 of the 5 patients who had been found free of aneurysms previously and had received 3D-CTA examinations for a second time one month later. The 3D virtual images produced by the virtual imaging system were clear and vivid, and they could reveal the location and size of the aneurysm and its relations to the parent artery and skull directly.</p><p><b>CONCLUSIONS</b>The imaging of 3D-CTA is convenient, reliable and fast in diagnosing intracranial aneurysms and can be regarded as the first choice for the diagnosis and treatment of ruptured intracranial aneurysms. Combined with the surgical plan system based on the VR image, 3D-CTA may obtain more imaging information about aneurysms.</p>

Correlation between power Doppler vascularity index and microvessel density in high-grade gliomas and adjacent edema / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the correlation between power Doppler vascularity index (PDVI) and microvessel density (MVD) and evaluate the angiogenesis in high-grade gliomas and the adjacent edema in patients with glioma using intraoperative power Doppler ultrasound (PDUS) during gross total resection.</p><p><b>METHODS</b>In 25 cases of high-grade gliomas undergoing gross total tumor resections, PDUS was performed intraoperatively and the regions of interest within the tumor and the adjacent edema were analyzed with Photoshop software to measure the tumoral and peritumoral blood flow quantified as PDVI. The tumoral and adjacent MVD were determined using immunohistochemical staining for CD34. The correlation between PDVI in the gliomas and the adjacent edema and MVD in the corresponding areas were analyzed using Spearman correlation test.</p><p><b>RESULTS</b>The measurement of both PVDI and MVD revealed significant difference in vascularity between the gliomas and the adjacent edema (t=0.000, P<0.01), and PDVI was positively correlated to MVD measurement (r=0.7248 in the tumors and r=0.6608 in the adjacent edema).</p><p><b>CONCLUSIONS</b>The difference in the vascularity between the tumor and adjacent edema allows their distinction by PDUS during operation for high-grade glioma. Intraoperative PDUS provides an accurate and reliable means for measuring vascularity in the glioma and the adjacent edema tissue.</p>

Sinerem labeling and MRI tracking of neural stem cells in vivo and in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To label rat neural stem cells (NSCs) with the complex of Sinerem, the ultrasmall superparamagnetic iron oxide (USPIO), and poly-L-lysine (PLL), and evaluate the feasibility of tracking the labeled cells with magnetic resonance imaging (MRI) in vitro and in vivo.</p><p><b>METHODS</b>Sinerem was incubated with PLL to obtain the complex of Sinerem-PLL. The mesenchymal stem cells (MSCs) isolated from the bone marrow of SD rats were cultured and induced to differentiate into the neural stem cells. The second-passage cells were cultured overnight with the Sinerem-PLL complex, after which Prussian blue staining and transmission electron microscopy were performed to observe the nanoparticles in the cytoplasm. Cell apoptosis assay was performed to assess the cell viability 1 day, 1 week, and 2 weeks after the labeling. Cell tracking with 4.7 MR system was carried out in vivo and in vitro using T(2)WI and T(2)*WI sequences.</p><p><b>RESULTS</b>The NSCs could be effectively labeled with Sinerem-PLL complex with the labeling efficiency exceeding 95%. Prussian blue staining showed numerous blue iron particles in the cytoplasm, and under transmission electron microscope, these particles accumulated in the endosomes/lysosomes. The labeling did not significantly affect the cell viability and proliferation. Remarkable low signal density changes of the labeled cells was seen on T(2)WI and T(2)*WI in vivo and in vitro.</p><p><b>CONCLUSION</b>NSCs can be effectively labeled with Sinerem-PLL complex, and MRI can be used to track the labeled cells in vivo and in vitro.</p>

Time course of calpain activity changes in rat neurons following fluid percussion injury and the interventional effect of mild hypothermia / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the time course of calpain activity changes in rat neurons following fluid percussion injury (FPI) under normothermia (37 degrees celsius;) and mild hypothermia (32-/+0.5) degrees celsius;.</p><p><b>METHODS</b>In vitro cultured rat neurons were subjected to FPI followed by application of mild hypothermia for intervention at different time points, and the changes in intraneuronal calpain activity following FPI and the interventional effect of mild hypothermia on calpain activity were evaluated by UV-spectrophotometry at different time points.</p><p><b>RESULTS</b>Remarkable changes occurred in calpain activity in the neurons following FPI at 37 degrees celsius;, and mild hypothermia produced obvious interventional effect on calpain activity in close relation to the timing of intervention initiation.</p><p><b>CONCLUSION</b>Intraneuronal calpain activity changes following FPI are involved in the pathological process of cellular injury, and mild hypothermia might offer protection against traumatic brain injury to some extent by regulating calpain activity. The interventional effect of mild hypothermia is associated with the timing of the intervention initiation.</p>

Melittin inhibits proliferation and induces apoptosis of malignant human glioma cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the anti-tumor effects of melittin against malignant human glioma cells in vitro.</p><p><b>METHODS</b>Two malignant human glioma cell lines (U87 and U251) were treated with melittin at various concentrations, and the cell growth inhibition and apoptosis were evaluated using MTT assay, flow cytometry and agarose gel electrophoresis.</p><p><b>RESULTS</b>Melittin could obviously inhibit the proliferation of the two glioma cell lines (P<0.05). At the concentrations of 1, 10, 20, 40, 80, 160, 200 mg/L, melittin resulted in U87 cell apoptosis rates of 12.80%, 16.92%, 22.69%, 34.05%, 41.82%, 59.87%, and 80.25%, and in U251 cell apoptosis rate of 11.61%, 16.21%, 22.03%, 30.57%, 41.10%, 58.33%, and 79.12%, respectively, showing a dose-dependent effect in its action of inducing cell apoptosis.</p><p><b>CONCLUSION</b>Melittin inhibits the proliferation and induces apoptosis of malignant human glioma cell lines in vitro.</p>

Effect of superparamagnetic iron oxide labeling on neural stem cell survival and proliferation / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effect of superparamgnetic iron oxides (ferumoxides) on the survival and proliferation of neural stem cells (NSCs) and determine the optimal ferumoxides concentration for labeling.</p><p><b>METHODS</b>Bone marrow stromal cells (BMSCs) were obtained from rat femoral marrow and cultured in vitro to induce their differentiation into NSCs. Ferumoxides labeling of the NSCs was performed with different final concentrations of ferumoxides, and the labeling efficiency and viability of the labeled NSCs were evaluated by Prussian blue staining, MTT assay, flow cytometry and transmission electron microscope.</p><p><b>RESULTS</b>The NSCs could be effectively labeled with ferumoxides with a labeling efficiency of around 90%. Prussian blue staining showed numerous fine granules with blue staining in the cytoplasm of the labeled NSCs, and the intensity of the blue staining was in positive correlation with the ferumoxide concentration for labeling. Transmission electron microscopy of the labeled NSCs revealed the presence of numerous vesicles spreading in the cytoplasm and filled with electron-dense magnetic iron particles. The ferumoxides vesicles increased with the labeling concentration of ferumoxides, and at the final concentration exceeding 25 microg/ml, ferumoxides vesicles in the NSCs gave rise to conglomeration which hampered observation of the cellular ultrastructure by transmission electron microscope. The results of flow cytometry and MTT assay demonstrated that the cell viability, proliferation, differentiation and apoptosis of the labeled cells were affected by ferumoxides at the concentration above 25 microg/ml, but such effects could be minimal at lower concentrations.</p><p><b>CONCLUSION</b>Ferumoxides might be feasible for in vitro labeling of the NSCs with the optimal concentration of 25 microg/ml.</p>

P-JAK2 and P-STAT3 protein expression and cell apoptosis following focal cerebral ischemia-reperfusion injury in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes in phosphorylated JAK2 and STAT3 protein expression of and cell apoptosis following focal cerebral ischemia-reperfusion injury in rats.</p><p><b>METHODS</b>A rat models of focal cerebral ischemia-reperfusion injury was established by middle cerebral artery occlusion using modified filament method. Immunohistochemistry and Western blot analysis were used to detect the expression of P-JAK2 and P-STAT3 proteins, and TUNEL assay was employed to examine the cell apoptosis.</p><p><b>RESULTS</b>P-JAK2 and P-STAT3 protein expression increased significantly after cerebral ischemia-reperfusion injury in rats. The immunoreactivity was prominent in the peripheral of the ischemic region and reached the peak level at 24 h of reperfusion, followed by slight decrement. The apoptotic cells increased obviously after cerebral ischemia-reperfusion injury, also reaching the peak level at 24 h of reperfusion.</p><p><b>CONCLUSION</b>The expression of phosphorylated JAK2 and STAT3 may be involved in the ischemic cellular events including apoptosis. JAK2/STAT3 signaling pathway plays a role in the pathophysiological process of cerebral ischemia/reperfusion cell injury and repair.</p>

Association of blood and cerebrospinal fluid IgG contents and severity of craniocerebral injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the association of blood and cerebrospinal fluid (CSF) IgG contents and the severity of craniocerebral injury.</p><p><b>METHODS</b>Totalling 143 patients with craniocerebral injury were divided into 3 groups according Glasgow Coma Scale (GCS) scores, namely the mild injury group with GCS score of 12-15 (n=41), moderate injury group with GCS score of 9-11 (n=71) and severe injury group (GCS score 3-8, n=32). Another 9 patients with congenital hydrocephalus were also recruited as the control group. The CSF and blood samples were collected from these patients to measure the IgG contents 4 and 14 days and 1, 2, and 6 months after the injury, respectively. Physical disabilities of the patients were estimated with Rappaport's disability rating scale (DRS), whose correlations with CSF and blood IgG contents were analyzed.</p><p><b>RESULTS</b>In the early stage of moderate to severe brain injury, the IgG content was lowered significantly in the blood but increased in CSF as compared with the control patients (P<0.05), and the changes in CSF and blood IgG displayed a significant correlation with the severity of the injury (r=0.950, P<0.01). During the recovery of severe brain injury, DRS score was in inverse correlation with blood IgG content but in positive correlation with CSF IgG content (Spearman's correlation coefficient of 0.800, P<0.05).</p><p><b>CONCLUSION</b>In the early stage of brain injury, detection of blood IgG content may help with the assessment of the injury severity. During the recovery of the injury, dynamic monitoring of blood and CSF IgG contents provides clues of the outcome of the patients and benefit the modification of the treatment plan.</p>

Lack of telomerase activity in rabbit bone marrow stromal cells during differentiation along neural pathway / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate telomerase activity in rabbit bone marrow stromal cells (BMSCs) during their committed differentiation in vitro along neural pathway and the effect of glial cell line-derived neurotrophic factor (GDNF) on the expression of telomerase.</p><p><b>METHODS</b>BMSCs were acquired from rabbit marrow and divided into control group, GDNF (10 ng/ml) group. Cytokine.NSCs medium (prepared by our lab, Patent No. ZL02134314. 4) supplemented with 10 percent fetal bovine serum (FBS) was used to induce BMSCs differentiation along neural pathway. Fluorescent immunocytochemistry was employed to identify the expressions of Nestin, neuron-specific endase (NSE), and gial fibrillary acidic protein (GFAP). The growth curves of the cells and the status of cell cycles were analyzed, respectively. During the differentiation, telomerase activities were detected using the telomeric repeat amplification protocol-enzyme-linked immunosorbent assay (TRAP-ELISA).</p><p><b>RESULTS</b>BMSCs were successfully induced to differentiate along neural pathway and expressed specific markers of fetal neural epithelium, mature neuron and glial cells. Telomerase activities were undetectable in BMSCs during differentiation along neural pathway. Similar changes of cell growth curves, cell cycle status and telomerase expression were observed in the two groups.</p><p><b>CONCLUSIONS</b>Rabbit BMSCs do not display telomerase activity during differentiation along neural pathway. GDNF shows little impact on proliferation and telomerase activity of BMSCs.</p>

Effect of photodynamic therapy with 5-aminolevulinic acid on human gastric cancer cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy (PDT) on MGC-803 human gastric cancer cells in vitro.</p><p><b>METHODS</b>MGC-803 human gastric cancer cells were treated with 5-ALA at various concentrations followed by laser irradiation. The cells were also treated with 5-ALA at the same concentration before laser exposure at various doses. PDT-induced phototoxicity of the cells was determined by MTT assay.</p><p><b>RESULTS</b>After laser exposure of the cells at the same dose (25.0 J/cm(2)), the cell survival rates decreased significantly with incubation of the cells with 5-ALA at 0.25, 0.5, 1.0, 2.0 and 4.0 mmol/L, respectively (F=266.39, P<0.001), but 2.0 and 4.0 mmol/L ALA showed no significant difference in lowering the cell survival rates (P>0.05). Following treatment with the same 5-ALA concentration (1 mmol/L), the cell survival rates decreased in response to increased laser doses (at 6.25, 12.5, 25.0, 50.0, and 100 J/cm(2), respectively, F=226.31, P<0.0001). Without laser exposure, the survival rate of the cells did not significantly change for different 5-ALA concentrations (F=0.79, P=0.5383), nor did it undergo obvious variation in response to different laser doses without 5-ALA incubation (F=0.61, P=0.6551).</p><p><b>CONCLUSIONS</b>The damage of MGC-803 cells by PDT increases with 5-ALA concentration within a relative lower range and is proportional to the laser doses delivered. Without 5-ALA treatment, the laser at the chosen dose cannot produce photodynamic effect and ALA itself is nontoxic. ALA-mediated PDT appears to be a promising therapy for gastric cancer.</p>

Evaluation of cerebral vasospasm resulting from subarachnoid hemorrhage with 1H-magnetic resonance spectroscopy / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the value of (1)H-magnetic resonance spectroscopy ((1)H-MRS) in evaluating cerebral vasospasm resulting from subarachnoid hemorrhage (SAH).</p><p><b>METHODS</b>Six dogs were subjected to autologous non-heparinized blood injection via cisternal puncture twice at one-day interval to establish models of SAH, and another 6 received injections with normal saline in an identical manner. (1)H-MRS scan was performed on the 3rd, 7th and 14th days after the injections to measure the changes of N-acetylaspartate (NAA), creatine (Cr) and choline (Cho). After the (1)H-MRS scan, all the dogs underwent brain digital subtraction angiography (DSA) for determining the basilar artery diameter.</p><p><b>RESULTS</b>DSA results on day 3 presented development of obvious vasospasm of the basilar artery, which was most evident on day 7 and recovered obviously on day 14. (1)H-MRS results demonstrated obvious changes of NAA, Cho and Cr on days 3 and 7 in SAH model group, and NAA declined to the lowest level on day 3 followed by gradual ascending till reaching the normal level on day 14. Cho decreased slightly on day 3, then increased and reached the peak level on day 7 and then decreased. Cr rose steadily from day 3 to 14, but since day 7, the rise slowed down obviously and Cr maintain a level not significantly different from that on day 14 (P>0.05). The functional results of (1)H-MRS were consistent with the DSA results.</p><p><b>CONCLUSION</b>(1)H-MRS can be used to monitor the development of cerebral vasospasm resulting from SAH as a good evaluation method for functional imaging.</p>

Apoptosis of glioma cell line U251 induced by small interfering RNA targeting survivin / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct recombinant expression vectors of small interfering RNA (siRNA) targeting survivin and investigate apoptosis of glioma cell line U251 mediated by the survivin-targeting siRNA.</p><p><b>METHODS</b>According to the sequence of the coding region of survivin gene, two strings of 19 nucleotides of inverted sequence flanking the loop sequence of two complementary 9-base oligonucleotides were designed and synthesized to form hairpin construct as the DNA templates for the target siRNA. The siRNA templates were cloned into siRNA expression vector pGenesil-1, and the resulted vector pGenesil-1/survivin was transfected into U251 cells using Metafectene following the standard protocols. Real-time PCR and Western blotting were performed to evaluate survivin gene silencing induced by siRNA transfection at the RNA and protein levels, respectively. Flow cytometry analysis with Annexin-V/PI double staining was used to determine the cell apoptosis.</p><p><b>RESULTS</b>Real-time RT-PCR and Western blotting revealed significantly lowered survivin expression at both RNA and protein levels in transfected U251 cells, which exhibited a significantly higher apoptosis rate after transfection as shown by flow cytometry analysis.</p><p><b>CONCLUSION</b>RNA interference mediated by the siRNA expression vector pGenesi-l/survivin can significantly reduce survivin expression and induce remarkable apoptosis in U251 cells.</p>

Effect of N-acetyl-cysteine and depakine pretreatment on ferrous chloride-induced membrane potential and peroxidate changes in rat cortex neurons / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of N-acetyl-cysteine (NAC) and depakine (DP) on the changes of membrane potential and peroxidate in rat cortex neurons exposed to ferrous chloride (FeCl(2)).</p><p><b>METHODS</b>Cultured cortex neurons of newly born SD rats were randomly divided into control group (PBS group), model group (FeCl(2) group), NAC pretreatment group (NAC group), DP pretreatment group (DP group) and NAC+DP pretreatment group (NAC+DP group). In the latter three groups, NAC (0.08 mg/ml) and DP (0.1 mg/ml) were added in the cell culture 2 and 3 h before FeCl(2) (1 mmol/L) exposure, respectively. After exposure to FeCl(2), the membrane potential of the neurons was detected with fluorescent dye DiBAC4(3) (bis-(1,3-dibutylbarbituric acid) trimethine oxonol), and the peroxidate level with 2,7-dichlorofluorescin diacetate (H(2)DCF) by laser confocal scanning microscope (LCSM) and nuclear factor-KappaB (NF-KappaB) level with immunocytochemistry.</p><p><b>RESULTS</b>Compared with FeCl(2) group, the expression of NF-KappaB and peroxidate level in the neurons were decreased significantly in NAC and NAC+DP groups (P<0.01), but not in DP group (P>0.05). FeCl(2) depolarized the membrane potential and increased the expression of NF-KappaB in the neurons. Compared with FeCl(2) group, significant changes in the membrane potential were observed in DP and NAC+DP groups (P<0.01) but not in NAC or PBS group (P>0.05).</p><p><b>CONCLUSION</b>Both NAC and DP can protect the neurons from FeCl(2)-induced damage but through different pathways, and their combined use can significantly alleviate neuronal damages due to FeCl(2) exposure. Antioxidants such as NAC in combination with antiepileptic drugs may produce favorable effect in prevention and treatment of posttraumatic epilepsy.</p>

Construction of eukaryotic expression vector with brain-derived neurotrophic factor receptor trkB gene / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To construct an eukaryotic expression vector carrying rat brain-derived neurotrophic factor receptor trkB gene.</p><p><b>METHODS</b>Using the total RNA isolated from rat brain as template, the trkB gene was amplified by reverse-transcription-polymerase chain reaction (RT-PCR) with a pair of specific primers which contained the restrictive sites of EcoR I and BamH I. The amplified fragment of trkB gene was digested with EcoR I and BamH I, and then subcloned into cloning vector pMD18-T and expression vector pEGFP-C2 respectively. The recombinant plasmids were identified by restriction endonuclease enzyme analysis and PCR.</p><p><b>RESULTS</b>The amplified DNA fragment was about 1461 bp in length. Enzyme digestion and PCR analysis showed that the gene of trkB had been successfully cloned into vector pMD18-T and pEGFP-C2.</p><p><b>CONCLUSIONS</b>The trkB gene of rat has been amplified and cloned into the eukaryotic expression vector pEGFP-C2.</p>

Time window characteristics of cultured rat hippocampal neurons subjected to ischemia and reperfusion / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To explore cell death and apoptosis in rat hippocampal neurons at different time points after ischemia, hypoxia and reperfusion injury and to elucidate time window characteristics in ischemia neuronal injury.</p><p><b>METHODS</b>Hippocampal neurons were obtained from rat embryo and were cultured in vitro. The ischemia and reperfusion of cultured rat hippocampal neurons were simulated by oxygen-glucose deprivation (OGD) and recovery. OGD at different time points (0.25 h to 3.0 h) and then the same recovery (24 h) were prepared. Annexin V-PI staining and flow cytometry examined neuron death and apoptosis at different time after injury.</p><p><b>RESULTS</b>After OGD and recovery, both necrosis and apoptosis were observed. At different times after OGD, there were statistically significant differences in neuron necrosis rate (P < 0.05), but not in apoptosis rate (P > 0.05). At recovery, survival rate of hippocampal neurons further decreased while apoptosis rate increased. Furthermore, apoptosis rates of different time differed greatly (P < 0.05). Apoptosis rate gradually increased with significant difference among those of different time points (P < 0.05). However, 2 h after ischemia, apoptosis rate decreased markedly.</p><p><b>CONCLUSIONS</b>Apoptosis is an important pathway of delayed neuron death. The therapeutic time window should be within 2 h after cerebral ischemia and hypoxia.</p>