Objective To analyze neural activity of in rat prefrontal cortex with the use of nonnegative matrix factorization with sparseness constrains (NMFs) as a methodology and to study how to express neural ensemble with higher precision during working memory task.Methods Experiment data were obtained from neural population activity in the period 5 s before and after the working memory event.From the zero point,the neuronal firing times were binned in windows of 200 ms with 50 ms overlapping.The normalized neuronal bin-count matrix is decomposed by NMFs into mixing matrix and source component matrix with sparseness constraints.Meaningful components were extracted to reconstruct the input by an inverse of NMFs transform.Results By analyzing the ten groups of data from 2 rats,with the numbers of the sparse sources of 10 and 15 respectively,explicit neural ensembles with the feature components were obtained in the sparse reconstructed activity.Comparing to rate coding,the spatiotemporal location of neural ensemble was more precisely detected.Conclusion The working memory information is encoded with neural ensemble activity.NMFs could find the sparse firing pattern robustly in neuron population activity.NMFs removes much redundancy and demonstrate the possibility to express neural ensemble with higher precision compared with rate coding,which would be helpful to infer correlations between cortical firing pattern and working memory event.

20% . In both groups CH was induced with infusion of 0.01% sodium nitroprusside (NTP) to maintain MAP at 55-65 mm Hg. MAP, HR, CVP cardiac output were continuously monitored. Arterial blood samples were taken before (T0 ) and after AHH (T1 ) , 30 min after CH was induced (T2 ) and 30 min after tennination of CH (T3 ) for blood gas analysis and determination of plasma levels of electrolytes and ?2-microglobulin.Results The two groups were comparable with respect to the demographic data including age, body weight and height. In group Ⅰ pH was significantly decreased after AHH and CH (T1-3) compared to the baseline (T0 ) and was significantly lower than that in group Ⅱ . There was no significant difference in plasma K+ , Na+ , Ca2+ , Cl- and BE between the two groups. Plasma?2- MG decreased significantly after AHH (at T1 ) compared to the baseline value before AHH (T0) in group Ⅰ and was significantly lower than that ingroup Ⅱ at T1-3 . Conclusion Glomerular filtration rate decreases during controlled hypotension as shown by increased plasma?2-MG. AHH combined with CH can improve glomerular filtration rate while exerts no significant effects on blood gases and electrolytes.

Objective To investigate the distribution of free Ca 2+ and characterization of Ca 2+ channel in the cultured 11～15 week human embryonic retina. Methods The cells from 11～15 week embryonic retina were dissociated enzymatically and cultured on coated cover slides. Three weeks later, Fluo3, a Ca 2+ indicator, was added in Ca 2+ containing or no Ca 2+ Hepes buffer and incubated with retinal cells for 30 min, meanwhile with or without verapamil, perdipine, or dexamethasone adding. Ca 2+ staining and Ca 2+ transit before and after 10 ?mol/L or 50 ?mol/L KCl stimulation was observed and recorded using Zeiss LM510 confocal laser scanning microscopy. Results In response to K + exposure, a rapid rise of free Ca 2+ in cytoplasma and nuclei of neuron and glial cell was observed, but was repressed with the treatment of verapamil, perdipine, or dexamethasone. The obvious Ca 2+ influx from cytoplasma into nuclei was observed even in the absence of external Ca 2+ . Conclusion L type Ca 2+ channel was expressed and functionally matured in the cultured early stage human embryonic retina.

Objective To establish a culture system in vitro of fetal and adult human retinal neural cells provide a model for the basic research of retinal neural cells and the medicinal exploitation. Methods Fetal human retinas(10~13 weeks after conception) and adult human retinas(20~40 years old) were dissected, dissociated, and put into culture plate which was coated with polylysine or rat tail gel. Specific growth factor EGF?FGF? BDNF or NT-4 were added to the culture medium. BrdU incorporation, Tunnel assessment and immuno-histochemistry and immuno-fluorescent staining were applied to determine cells proliferation, apoptosis and identify the component of cultured cells. Results Fetal human retinal cells and adult human retinal cells survived for up to 100 and 180 days in vitro. The addition of EGF?FGF? BDNF or NT-4 promoted the survival of both fetal and adult retinal neurons and stimultated proliferation of fetal retinal cells. The neurons or the rate of ganglion cells was observed with higher percentage in the group with growth factor adding than the group without. Conclusion Fetal and adult human retinal cells can be maintained in vitro and the fetal cells also can be expanded, which are helpful to generate retinal neurons for basic research and drug exploitation. The exogenous growth factors added to the culture medium can promote survival, proliferation and differentiation of retinal cells in culture.

ObjectiveTo investigate the effects of epidermal growth factor (EGF),fibroblast growth factor(FGF), and bovine serum on proliferation and apoptosis of the cultured fetal human retinal cells.MethodsEGF and FGF were added or not to the medium of fetal human retinal cells cultured by bovine serum in vitro. The number of cells, bromodeoxyuridine(BrdU) incorporation and Tdt-mediated dUTP nick end labelling(TUNEL) were detected to determine the proliferation and apoptosis. Immunohistochemical staining of neuron specific enolase(NSE), Thy1.1, glial fibrillary acidic protein(GFAP) and scan electromicroscopy were performed to identify cell components. The expression of transcription factor c-fos, c-jun and apoptosis regulation factor bcl-2 and Bax were examined by immunohistochemical staining to explore the underlying mechanism.ResultsThe increased number of NSE and Thy1.1 positive cells and BrdU incorporation, and decreased apoptotic cells were found in the groups treated with EGF and FGF. Meanwhile, the up-regulation of c-fos, c-jun and bcl-2 were also found.ConclusionEGF and FGF can promote the survival and proliferation of cultured retinal cells by up-regulating the expression of c-fos, c-jun and bcl-2.

Objective To explore stimulative of posttraumatic growth(PTG) of head-injured patients associated with limb movement disorder,in order to provide reference for psychological nursing intervention.Methods Phenomenological methodology was used in the study.A semi-structured interview was conducted on seven head-injured patients with limb movement disorder recruited by purposive sampling method.Data were analyzed by Colaizzi's analysis procedure.Results Through interview,the following four themes were summarized:positive state of mind and coping style of patients; patients' high level of self-efficacy; social support; high quality of medical services.Conclusions In order to promote PTG of head-injured associated with limb movement disorder patients,nurses should strive to adjust the patient mentality and coping strategies,improve their self-efficacy levels,help patients get support from the community,at the same time should also focus on quality of medical services.

Proteolytic cleavage is one of the post-translational modifications and plays important roles in many biological processes, such as apoptosis and tumor cell metastasis. The identification of the cleavage events can improve our understanding of their biological functions in these processes. Although proteomic approaches using N-terminal labeling have resulted in the discovery of many proteolytic cleavages, this strategy has its own inherent drawbacks. Labeling of protein C-termini is an alternative approach. Here, we optimized the labeling procedure in the profiling protein C-termini by enzymatic labeling (ProC-TEL) and improved the labeling efficiency for the positive isolation of protein C-terminal peptides and mass spectrometric identification. We applied this approach to a complex protein mixture from Escherichia coli and identified many C-terminal peptides and internal cleaved peptides from more than 120 proteins. From the identified cleavages, we found several previously known internal proteolytic cleavage sites and many novel ones which may play roles in regulating normal biological processes. This work provides a potential new way, complementary to the N-terminomics, for the identification of proteolytic cleavages in complex biological systems.
Cathepsin A ; chemistry ; Protein C ; chemistry ; Protein Processing, Post-Translational ; Proteolysis ; Proteomics

OBJECTIVE To analyze the application of antibacterials in liver transplanted patients of our hospital in order to improve the rational use of antibacterials in perioperative period of liver transplantation.METHODS According to the criteria of DDD and DUI recommended by WHO,a retrospective study of the application of antibacterials in 82 patients with liver transplantation who discharged hospital during from Jun 2003 to Jun 2005 was made.RESULTS Among the 82 patients,100.0% patients had received antibacterials and 48 patients received combined medication,in which 45.10% used two kinds and 13.41% used three kinds.The longest medication time was 49 days while the shortest was 10 days.Nineteen antibacterials′ DUI were all less than one except meropenem whose DUI was 1.03.CONCLUSIONS This study proved that patients with liver transplantation in our hospital received rational antibacterials.

Objective To develop an HPLC-MS/MS method for simultaneous determination of xylazine and 2,6-xylidine in body fluid samples.Methods The samples were extracted by HLB SPE,separated by Waters Atlantis dC18 chromatographiccolumn,and then detected in the MRM scan ion mode under positive ionization condition.Results The recoveryrates of this method were between 70.5％ and 79.8％ with the range of RSD rfrom8.2％ to 10.5％.The limits of detection ofxylazine and 2,6-xylidine in blood and urine samples were 0.4 and 0.3 ng/mL,and the limits of quantitation were 1.2 and 1.0 ng/mL,respectively.Conclusion This method is of high sensitivity,good specificity and good reproducibility,and thus could besuitable for accurate quantification of xylazine in blood and urine samples.

Objective To study the relationship between common photoallergens and melasma.Methods Twenty allergens were selected according to the National Diagnostic Criteria for Photosensitive Dermatitis induced by cosmetics,National Diagnostic Criteria for Contact Dermatitis induced by cosmetics and National Diagnostic Criteria for Occupational Skin Diseases.Based on the standard procedures for photopatch test recommended by the British Photodermatology Group (BPG),photopatch test was performed on 50 patients with melasma and 30 normal controls.Results The positivity rate of photopatch test was 48.0%(24/50)in patients suffering from melasma,significantly higher than in the controls[23.33%(7/30),P<0.05].Conclusion Patients with melasma appear more likely to have positive photopatch test than normal controls.