The core problem of the brain-computer interface (BCI) based on neural signal is estimating neural firing rate from a spike train and then using neural population decoding algorithm to decode movement trajectory.In this artical, we review the theoretical basis of both classic and current firing rate estimations and compare the advantages and drawbacks of these methods. At the same time we also review the decoding algorithm which using neural firing rate to decode movement trajectory in brain- computer interface: population vector algorithm, linear filter and kalman filter. At last, some results applying these estimators of firing rate to decode arm movement in BCI are introduced. The results show apparently different performance of the different firing rate estimators, while minimal differences are observed in the actual application of BCI.

Aiming at local field potential, the present paper introduces a method of estimating lag of neuron activities between brain areas based on windowed Harmonic wavelet transform (WHWT). Firstly, the WHWT of signals of two brain areas are calculated. Secondly, the instantaneous amplitude of the signals is calculated and finally, these amplitudes are cross-correlated and the lag at which the cross-correlation peak occurs is determined as the lag of neurons activities. Comparing with amplitude cross-correlation based on Gabor wavelet transform (GWT) or Hilbert transform (HT), this method is more precise and efficient in estimating the directionality and lag.
Brain ; physiology ; Humans ; Neurons ; physiology ; Wavelet Analysis

Objective:To observe the clinical characteristics of elderly patients with liver failure complicated with fungal infection,and to analyze the factors influencing the prognosis.Method:117 cases of elderly patients with liver failure,who were treated in our hospital from May 2013 to May 2015,were selected as object,according to whether combined with fungal infection,the patients were divided into Fungal infection group (57 cases) and non fungal infection group (60 cases).The differences of liver function index,treatment effective rate and mortality were observed between the two groups;To compare the prognosis of patients with different clinicopathological features,and to explore the factors influencing the prognosis of patients.Results:The scores of ALT,AST and DBIL in patients with fungal infection were significantly higher than those without fungal infection,and the difference was statistically significant (P＜0.05);The effective rate of the treatment group was significantly lower than that of the non fungal infection group,the mortality rate was higher than that of the non fungal infection group,the difference was statistically significant (P＜0.05);The death rate of patients with age was more than or equal to 70 years of age,with diabetes,with fungal infection were higher (P＜0.05);Logistic regression analysis showed that combined with diabetes mellitus,combined with fungal infection was an independent prognostic factor for elderly patients with liver failure (OR=2.982,4.817,P＜0.05).Conclusion:Liver function injury is severe in elderly patients with liver failure,the mortality rate is high,and fungal infection is more serious,and diabetes and fungal infection are risk factors for mortality.

BACKGROUND: Skeletal muscle-derived stem cells (MDSCs), another adult pluripotent stem cells, have become a hot topic in the field of gene therapy and cell-based tissue engineering. It has wide prospect in treating stress incontinence by periurethral injection of patients' MDSCs.OBJECTIVE: To investigate the method of culturing MDSCs in vitro so as to provide experimental basis for treating stress incotinence by injecting MDSCs.DESIGN: Repeated observation.SETTING: Department of Reproductive Medical Center and Department of Urology, Renmin Hospital of Wuhan University.MATERIALS: This experiment was conducted at the Laboratory of Department of Urology , Renmin Hospital , wuhan University from December 2003 to May 2004. Totally 20 female SD rats , aged 4 to 6 weeks , were involved . Type- Ⅺ pancreatin, collgenase , pancreatin ,polylysine (Sigma), dispase enzyme (Gibco) , chick embryo extract (self made).METHODS: ① Rats were anesthetized intraperitoneally with 10 g/Lpentobarbital sodium (30 g/kg). Under aspetic condition, gastroeneminus were isolated and immediately put into pre-cooled DMEM media (Gibco)containing antibiotics and then removed into the hood. After washed with D-hank's solution three times, muscle biopsies were removed of fascia,tendon, nerve and blood vessels and minced into small pieces about 1-3 mm3,and then transferred into a centrifugation tube. 0.2% collgenase-type Ⅺ(Sigma) and 0.1% pancreatin were added to the left tissue . Skeletal muscle cells of the rats were isolated with collagenase. ② Differential attachment was used to purify the skeletal muscle cells of the rats. After screened with cell screen cloth , cell suspension was transferred into a polylysine-coated flask and cultured at 37 ℃ in a humid atmosphere with 0.05 CO2 in air for 1 hour. All the cells that did not adhere to the flask were then transferred to another flask with new culture medium and cultured for approximately 1 hour at 37 ℃ .Again,the non-adhering cells were transferred to another flask and were incubated at 37 ℃ overnight.The technique was carried out for an additional 4-5 days. This operation was repeated every 24 hours until the fifth day. Those cells attached on days 5-6 were MDSCs.③ After they grew with 70% confluence , the cells were digested with trypsin and passaged at the ratio of 1:2. After digestion, the generative cells were inoculated to the culture plate with 6-well cover glass. Growing culture medium was added and cell slide was prepaared 24 hours later. The expression of specific protein antigen and stem cell antigen-1 of the cultured cells were identified with immunohistochemical staining.MAIN OUTCOME MEASURES: Morphology and identification of MDSCs.RESULTS: ① Morphology of MDSCs: Cells isolated from skeletal muscle tissue took the form of spheres and had high refraction. When subcultured,they began to adhere at the 12th hour, at that time they were still round,and complete their attachment at the 48th hour. Then they began to expand and ultimately became fusiform-shaped or spindle-shaped, having two poles and small size. As time going, they fused with each other to form mature poly-nuclear myotubes. ② Identification results of muscle-derived stem cells: MDSCs were desmin and stem cell antigen-1 (Sca-1) positive specific for some stem cells. Red fluorescence effluenced from cytoplasm was found under the fluorescence microscope and the positive rate reached 90%.CONCLUSION: MDSC belongs to adult stem cells and has the advantages of rich source, low immunogenicity and long survival after transplantation. High-purity muscle-derived stem cells can be obtained through primary culture , and immunohistochemical technique can identify muscle-derived and specific characteristics of stem cells, so it has a broad application perspective in tissue engineering and gene therapy.

ObjectiveTo investigate the mechanism by which cyclosporine A downregulates transcription of interferon-? gene after murine orthotopic liver transplantation.Methods Orthotopic murine liver transplantation model was employed and rats were divided into 3 groups. GroupⅠ: syngeneic control (Wistar-to-Wistar); GroupⅡ: acute rejection (SD-to-Wistar). GroupⅢ: acute rejection treated with cyclosporine A (SD-to-Wistar+CsA). EMSA was employed to analyze NFAT and NF-?B DNA-binding activity of splenocytes, RT-PCR was employed to analyze IFN-? mRNA transcription intragraft on 1,3,5,7,12 day posttransplant in each group, respectively. Histopathological examination was also performed for reference.Results In comparison to groupⅠ, NFAT and NF-?B DNA-binding activity of splenocytes in groupⅡincreased significantly( P

Objective To study the role of 1,25-dihydroxyvitamin D3 in preventing allograft acute rejection in rat orthotopic liver transplantation. Method Rats receiving orthotopic liver transplantation were divided into groupⅠ: syngenic control (Wistar-to-Wistar); GroupⅡ:acute rejection (SD-to-Wistar). GroupⅢ: acute rejection treated with cyclosporine; GroupⅣ: acute rejection treated with 1,25-(OH)_ 2 D_ 3 . Liver function, rejection index and IFN-? mRNA, IL-10 mRNA expression level were monitored on d1,5,7,15,30 posttransplantation. Results Survival of recipients in group Ⅳ was significantly prolonged (vs group Ⅱ, P

AIM: To investigate the role of NFAT in cyclosporine A downregulating IFN-? gene transcription after liver transplantation. METHODS: Rat orthotopic liver transplantation model was employed and 3 groups of experiments were performed in this study. GroupⅠ: syngeneic control (Wistar-to-Wistar); GroupⅡ: acute rejection (SD-to-Wistar). GroupⅢ: acute rejection treated with cyclosporine A intramuscularly (SD-to-Wistar+CsA). EMSA and RT-PCR were used to analyze NFAT activity of splenocytes and IFN-? gene transcription intragraft of recipients with or without CsA treatment after liver transplantation. Histopathological assessment was also performed for reference. RESULTS: No noticeable rejection was detected in GroupⅠ while only low level of IFN-? mRNA transcription and faint NFAT activity were measured. In contrast, a marked rejection reaction was demonstrated from day3 postoperation in GroupⅡ. IFN-? mRNA transcription was significant and NFAT activity was intensive. In comparison to GroupⅡ, rejection grade in Group Ⅲ significantly decreased (P

BACKGROUND:An effective freezing-thawing technique is crucial for the clinical application of human umbilical cord mesenchymal stem cells(UC-MSCs).OBJECTIVE:To investigate biological characteristics of UC-MSCs after cryopreservation.METHODS:UC-MSCs were isolated from human umbilical cord and frozen in liquid nitrogen.The survival rate and the suppressive effect of γ-interferon(IFN-γ)of cryopreserved-thawed and fresh human UC-MSCs were compared.Furthermore,the multiple potentials and phenotype of UC-MSCs were estimated after cryopreservation.RESULTS AND CONCLUSION:There was no significant difference between cryopreserved-thawed and fresh human UC-MSCs on the survival rate and the suppressive effect of IFN-γ of peripheral blood mononuclear cells(PBMCs).After cryopreservation,human UC-MSCs had the potential differentiation and the phenotype of mesenchymal stem cells.

Objective To investigate the effect of platelet-derived growth factor-D (PDGF-D) on the prostate cancer cells migration and its possible mechanism. Methods The expressions of PDGF-D in LNCaP and PC-3 cells were detected with western blot.PDGF-D siRNA was synthesized according to mRNA sequence of PDGF-D gene and was transfected into PC-3 cell.The cells were treated with PDGF-D and PDGF-D siRNA,the cell migration was examined by Boyden chamber migration assay.The expression changes of VEGF and MMP-9 mRNA were detected by RT-PCR. Results The results of western blot indicated that the PDGF-D protein expression level was lower in LNCaP cells (29.47 ± 1.68) than that in PC-3 cells (63.43 ±2.10),(P ＜ 0.05).PDGF-D siRNA could down-regulate the PDGF-D protein expression in the transfected group (35.19 ± 1.51).The exogenous PDGF-D could promote migration of LNCaP and PC-3cells,and up-regulate the expression of VEGF,MMP-9 mRNA in PC-3 cells (P ＜ 0.05,compared with control group).PDGF-D siRNA inhibited PC-3 cells' migration and decreased the level of VEGF,MMP-9mRNA expression (0.72 ± 0.09 vs 0.43 ± 0.18,0.65 ±0.07 vs 0.22 ± 0.08) (P ＜ 0.05). Conclusion PDGF-D is involved in the promotion of prostate cancer invasion and angiogenesis.

A cross-sectional study in 116 patients with polycystic ovary syndrome (PCOS) was carried out by using the short-form-36 health survey (SF-36), serf-rating anxiety scale ( SAS), and self-rating depression scale (SDS) from January 2008 to April 2008 in our reproduction center. In comparison with the healthy controls, the PCOS patients showed decreased quality of life (QOL) for all items of SF-36 (P<0.05) except for body pain or role-physical scales. The differences in SAS and SDS between the PCOS and the healthy controls were statistically significant (P<0.05). Our study results confirm the negative impacts of PCOS over the quality of life;subfertility, obesity, hirsutism, acne, complications, menstrual irregularity and educational levels might contribute to the reduced QOL.