Extraction and Separation of Boron in Anhydrite and Gypsum Minerals and Its Isotopic Measurement by Thermal Ionization Mass Spectrometry / 分析化学

The anhydrite and gypsum are the main sulfate minerals during evaporation of seawater or lake.They record the information about relative hydrogeology and the composition of mother liquor.Boron is diffluent element, and often occurs in all kinds of evaporites.Presently, the boron isotope has been applied widely in mineral deposits forming, geochemistry and palaeoenvironment.However, there is little research about characteristic of boron isotope in anhydrite and gypsum minerals, because of the low content of boron and micro-solubility in water and hydrochloric acid.This study developed a method of extracting and purifying boron in anhydrite and gypsum by phase transformation and ion-exchange.Firstly, the samples were mixed with ammonium hydrogen carbonate to transform the calcium sulfate to calcium carbonate.And diluted hydrochloric acid (1 mol/L) was added to resolve calcium carbonate.The percent conversion was about 85%in the first stage, and up to complete resolution by repeating this process.Secondly, boron specific ion-exchange resin ( Amberlite IRA 743 ) was used to gather the boron ions fully and further refined the samples with more than 1 μg of boron by anionic and cationic resin mixed by Ion Exchange Ⅱ and Dowex 50 W × 8.Finally, according to the modified method by He, the values of boron isotope were determined by TIMS.The boron content is analytically pure gypsum was 3.501 ± 0.128 μg/g ( n=12 , RSD=3.6%) and the average recovery was 100.47%.Besides, the δ11B value of analytically pure gypsum added with NIST SRM 951 was 17.98‰±0.21‰ (n=3, RSD=1.2%).This method has good repeatability and can meet the requirements of boron isotopic measurement of anhydrite and gypsum.

Clinicopathological analysis of 19 cases with congenital nonprogressive hemangiomas / 临床与实验病理学杂志

Purpose To investigate the clinicopathological features and differential diagnosis of congenital nonprogressive hemangiomas in children.Methods The clinic pathologic data and follow-up results of 19 cases of congenital nonprogressive hemangiomas were collected.The histopathologic features of congenital nonprogressive hamangiomas were observed with HE staining and immunohistochemistry of EnVision two-step.Results Of the 19 patients,13 were males and 6 were females,with an average age of 52.4 months and medium age of 48 months.9 cases occurred in the limbs and trunk,10 lesions were located in head and face included 1 case with multifocal lesions.Grossly,the specimens were irregular solid mass with range from 0.4 cm to 7 cm in maximum diameter.Microscopically,the lesions were composed of capillary lobules that separated by abnormal dense fibrotic dermal stroma typically containing a prominent component of large vessels.Immunohistochemically,the tumor cells were positive for CD31,CD34,and WT1,but negative for D2-40 and GLUT1.All eases underwent surgical resection,and the follow-up period was 1-24 months.There was no recurrence or metastasis.Conclusion Congenital nonprogressive hemangioma is a rare benign vascular tumor in children,with characteristic clinical and pathologic features.So the exact diagnosis is very important for both pathologists and clinicians.

Gender difference of attentional network in 5-year old children / 中国心理卫生杂志

Objective:To investigate gender differences in the attentional network in 5-year-old children.Methods:A totally of 70 healthy children [31 girls,(62.5 ± 2.6 months old;39 boys,(63.3 ± 2.8) months old] from the top class of kindergarten were enrolled in the study.A modified version of the Attention Network Test (ANT) was used to assess the attentional networks (alerting,orienting,and executive control).Results:The mean rate of accuracy was higher than 90％.A significant gender difference was found in the alerting network,boys scored higher than girls [(139 ± 54) ms vs.(109 ± 49) ms,P ＜ 0.05].No gender difference was found in the orienting or executive control networks (P ＞ 0.05).Conclusion:It suggests that 5-year-old children are fully capable of completing the attentional networks test,and the 5-year-old boy's alert function may be stronger than that of girls.

Clinical observation of 3 minutes dark-room provocative test in patients with laser peripheral iridectomy in the fellow eyes of acute angle-closure glaucoma / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To observe related biological parameters of 3 minutes dark-room provocative test in patients with laser peripheral iridectomy(LPI) in the fellow eyes of acute primary angle-closure (APAC) by ultrasound biomicroscopy (UBM).To explore the risk factors in primary angle closure suspect(PACS) patients with progressive angle closure after LPI.METHODS: Seventy-eight eyes of APAC patients without peripheral anterior synechia were selected.Each eye underwent 3 minutes dark-room provocative test after LPI.Anterior segment parameters, including anterior chamber depth (ACD), anterior chamber angle open distance500 (AOD500), peripheral iris thickness (PIT), iris convex (IC), the position of iris insertion and trabecular-ciliary process distance (TCPD), and the number of positional angle closure(NPAC) were observed and analyzed by statistic methods.RESULTS:Patients with APAC were examined by UBM after LPI and 26 eyes(33%) occurs at least one positional angle closure,19 eyes(24%)were positive in 3 minutes dark-room provocative test among them.It occurs a positive relationship between the elevation intraocular pressure and the number of positional angle closure in dark-room provocative test(r=0.84, P<0.01).AOD500, IT and IC were significantly changed from normal light to darkroom between positional angle closure positive group and positional angle closure negative group(all P<0.01).In single factor analysis, AOD500(P=0.003), IT(P=0.012), IC(P=0.043), TPCD(P=0.015), the position of iris insertion(P=0.024) were correlative factors of positive results.In multiple-factor analysis, only IT(P=0.011), TPCD(P=0.009), iris root attachment points(P=0.02) were independent risk factors of positive results.CONCLUSION:A certain proportion of patients with PACS after LPI appeared positional angle closure in a dark room.Peripheral iris hypertrophy, anterior displacement of the ciliary body and iris root attachment points are vital risk factors.Long-term follow-up study and intervention treatment are required in these patients after LPI.

Clinical observation of needle revision and 5-fluorouracil subconjunctive injection for the dysfunctional filtering blebs / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the efficacy and safety of needle revision with 5-fluorouracil (5-FU) on the dysfunctional filtering blebs after trabeculectomy and to assess the factors that may impact the success. METHODS:Eighty- three eyes in 76 patients underwent the needle revision and 5-FU subconjunctive injection for the dysfunctional blebs after trabeculectomy and were followed up for 12mo. The intraocular pressure ( IOP), the number of drugs, corneal endothclium, bleb morphology and complications were observed and recorded. RESULTS: IOP decreased significantly from 35. 3 ±5. 8mmHg(1kPa = 7. 5mmHg) of pre - needling to 17. 0 ±4. 3mmHg of post - needling ( P CONCLUSION: The needle revision combined with 5-FU is a safe, effective and simple method. Dysfunctional blebs should be treated early after trabeculectomy.

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>

Free perforating flap of peroneal artery for repairing the forefoot skin defects / 中国骨伤

<p><b>OBJECTIVE</b>To explore the clinical techniques and effects of repairing skin defects of the forefoot by free perforating flap nourished by peroneal artery.</p><p><b>METHODS</b>From June 2007 to June 2011, 11 patients with skin and soft tissue defects of the forefoot were repaired by free peroneal artery perforating flap in emergent or subemergent. There were 10 males and 1 female with an average age of 28.6 years old ranging from 23 to 46 years old. Among them, 4 cases injured for traffic accidents, 3 for crush and 4 for machine strangulation. In all cases, the defect area of forefoot tissue varied from 2.0 cm x 4.0 cm to 4.0 cm x 8.5 cm,and the adopted area varied from 2.5 cm x 4.5 cm to 4.0 cm x 9.0 cm. The operation time was from 6 to 96 h (averaged 31.8 h). The blood vessels were anastomosed end-to-end.</p><p><b>RESULTS</b>All of the transferred free flaps survived uneventfully. Nine of them were successfully followed up from 6 to 24 months. The appearance, elasticity and functions of flaps were satisfied accompanied with slight damage of donor site although seemed bloated. The smaller donor site could be intimately seamed if necessary.</p><p><b>CONCLUSION</b>The vessels anatomy of knee with antegrade extended peroneal artery was relative constant with a moderate thickness and simple operation, is useful to repair small or middle areas of skin defects in forefoot.</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>

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>

Investigation and thought on the teaching modes of the course of guide to learn in nursing under graduate education / 中国实用护理杂志

Objective To investigate the teaching modes of the course of guide to learn in undergraduate nursing students in order to improve their quality of leaning.Methods Questionnaire survey and interview were conducted to collect the students'general appraisal on learning Science and teaching content and teaching modes as well as ingathering and suggestions of the course.Results Totally 79.5%among 117 students thought it necessary to open the course of Learning Science.96.6%students considered ten subjects of the course reasonable.83.8%students were satisfied with the alternate five-teachers'teaching modes.The most digestible teaching approach Was illustration,and the most valuable experience wag how to regulate the psyehology of learning.Conclusions The course of guide to learn in nursing undergraduate education has positive significance.Nursing educators should always explore and improve the teaching mode of this course so as to help students develop SOundly.

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>

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>

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>

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>

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>

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>

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>

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>