In our previous work, we found that trivalent dimethylarsinous acid (DMA(III)) have high affinity binding to cysteine residue 13 of rat hemoglobin. However, it is still unknown why arsenic intermediate metabolite DMA(III) has high binding affinity for Cysl3 but not for other cysteine residues 93, 140, 111 and 125. In order to better understand the molecular mechanism of DMA(III) with rat hemoglobin, we have done current study. So, SD rats were divided into control and arsenic-treated groups randomly. Arsenic species in lysate of red blood cells were analyzed by HPLC-ICP-MS, and then determined by a hybrid quadrupole TOF MS. In addition, trivalent DMA(III) binds to different cysteine residues in rat hemoglobin alpha and beta chains were also simulated by Molecular Docking. Only Cys13 in alpha chain is able to bind to DMA(III) from the experiment results. Cys13 of alpha chain in rat hemoglobin is a specific binding site for DMA(III), and we found that amino acids compose pockets structure and surround Cys13 (but not other cysteine residues), make DMA(III) much easy to bind cysteine 13. Taken together, the DMA(III) specific binding to Cys13 is related to spatial structure of Cys13.

BACKGROUND:Previous studies have shown that composite scaffold of chitosan and poly-L-lactic acid has good biocompatibility with some cells. OBJECTIVE:To study the biocompatibility of poly-L-lactic acid reinforced by chitosan and olfactory ensheathing cells. METHODS:In experimental group, olfactory ensheathing cells from Sprague-Dawley rats aged 1-3 days were incubated onto chitosan-reinforced poly-L-lactic acid film. And in control group, olfactory ensheathing cells were co-cultured with poly-L-lysine. The proliferative ability of olfactory ensheathing cells was detected and the cells were observed with immunofluorescence histochemical staining at 1, 3, 5, 7 days after culture. RESULTS AND CONCLUSION:Olfactory ensheathing cells could survive on the chitosan-reinforced poly-L-lactic acid film, and the cytotoxic grade wasⅠ. Morphology of the cells in the experimental group was round or oval, with little processes and the cells aggregated into groups. One day after implantation, the periphery cells of the mass extended short projections and gradual y spread outward;3 days after implantation, the cells spread and most of the cells generated projections, most of which were bipolar or tri-polar;5 days after implantation, cel processes significantly extended, most cells were bipolar and tri-polar cells, while some were oval cells and irregular triangular cells;7 days after implantation, the cel density increased, and cel processes extended. Cel morphology of the control group had similar characteristics as the experimental group. There was no obvious difference between the control and the experimental group in number, perimeter or area of the cells (P>0.05). It showed that chitosan-reinforced poly-L-lactic acid had good biocompatibility with olfactory ensheathing cells.

BACKGROUND: Fibrin glue has been demonstrated to function as a kind of biomaterial with high quality. It has been used in nerve tissue engineering and proved to be a kind of scaffold for some cells.OBJECTIVE: To explore the biocompatibility of fibrin glue and olfactory ensheathing cells (OECs).DESIGN, TIME AND SETTING: An in vitro control trial based on cytology was performed at the Institute of Neurobiology,Nantong University from August 2007 to February 2008.MATERIALS: Fibrin glue was made of fibrin and catalyst, and OECs derived from rats' olfactory bulb were normally primary-cultured.METHODS: OECs were divided into control (OECs clone spheres were cultured alone) and in fibrin glue (OECs clone spheres were cultured and combined with fibrin glue) groups. After 1 week of culture, the proliferation of OECs were observed by convert microscope and detected by S-100 immunofluorescence histochemical staining.MAIN OUTCOME M EASURES: OECs morphology, cell count, the area of the cell bodies and the perimeter of the cell were determined.RESULTS: OECs could survive, migrate in fibrin glue, and float in the fibrin glue in the lower layer. After 7 days of incubation, cell body exhibited fusiform or triangle, predominantly bipolar or bipolar. The number of the S-100 positive cells was more, and cell bodies were larger in fibrin glue group than control group (P < 0.05). However, there was no obvious difference between two groups in cell perimeter (P > 0.05).CONCLUSION: Fibrin glue has good biocompatibility with OECs, and OECs can survive and migrate in fibrin glue.

Objective To observe the efficacy of combination therapy of calcium dobesilate dispersible and monosialotetrahexosylganlioside sodium on interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1) in elderly patients with painful diabetic peripheral neuropathy.Methods From January 2012 to May 2017,in the Second People's Hospital of Lianyungang 70 patients of painful diabetic peripheral neuropathy,aged ≥60 years,were analyzed in this study.They were randomly divided into observation group (35 cases) and control group (35 cases).The observation group was treated with 40mg monosialotetrahexosylganlioside sodium dissolved in 250mL physiological saline,intravenous infusion per day,and oral calcium dobesilate dispersible 0.5g twice a day for two weeks.The control group was treated with methylcobalamin injection 0.5mg per day for two weeks.The clinical treatment effects and levels of IL-6 and MCP-1 were observed and compared between the two groups.Results After two weeks of treatment,the MDNS and MNSI scores of the observation group [(13.09 ± 5.38)points,(2.53 ± 1.19)points] were significantly lower than those of the control group [(18.31 ± 6.13) points,(4.19 ± 1.05) points,t =2.036,2.365,all P ＜ 0.05] and those before treatment [(21.26 ± 4.28) points,(5.40 ± 0.89) points,t =3.251,3.698,all P ＜ 0.05].The VAS-PI scores in the observation group [(6.24 ± 1.25) points,(4.13 ± 1.69) points] were significantly lower than those in the control group[(7.26 ± 1.28) points,(6.34 ± 2.65) points] at the first and second week (t =3.265,5.395,all P ＜ 0.05).The serum levels of inflammatory cytokines IL-6 and MCP-1 in the observation group [(15.16 ±0.88) ng/L,(157.19 ± 11.22) ng,/L] were significantly lower than those in the control group[(17.87 ± 1.19) ng/L,(198.21 ± 12.07)ng/L,t =2.152,1.365,all P ＜0.05]and those before treatment[(20.26 ± 1.05) ng/L,(260.44 ± 13.63) ng,/L,t =1.235,0.965,all P ＜ 0.05].Conclusion Combination of calcium dobesilate and mono-sialotetrahexosyl ganglioside may alleviate the sensory and pain sensations in patients with painful diabetic peripheral neuropathy,possibly by reducing the level of inflammatory cytokines IL-6 and MCP-1.

The present research was aimed to explore the biocompatibility of IKVAV self-assembling peptide nanofiber scaffold with olfactory ensheathing cells (OECs) of rats. The OECs were seeded onto the surface of coverslips covered with IKVAV self-assembling peptide nanofiber scaffold hydrogel (2D culture system), and implanted within IKVAV self-assembling peptide nanofiber scaffold hydrogel (3D culture system), respectively. The adhesion, viability of OECs were observed with inverted microscope. Then the characteristics for survival and adhesion of cells by image processing were observed, and statistical analysis on the number of S-100 positive cell, the area of the cell bodies and the perimeter of the cell and MTT method were carried out. It was found that the OECs could survive and migrate in IKVAV self-assembling peptide nanofiber scaffold. The result of the cell MTT exam, of the shape and quantity of cells had no significant difference compared to those of the OECs cultured with poly-L-lysine (PLL). It has been proved that IKVAV self-assembling peptide nanofiber scaffold has good biocompatibility with rat OECs.
Animals ; Animals, Newborn ; Biocompatible Materials ; chemistry ; Cell Proliferation ; Cells, Cultured ; Hydrogel, Polyethylene Glycol Dimethacrylate ; chemistry ; Laminin ; chemistry ; Nanofibers ; chemistry ; Olfactory Bulb ; cytology ; drug effects ; Peptide Fragments ; chemistry ; Rats ; Rats, Sprague-Dawley ; Tissue Engineering ; methods ; Tissue Scaffolds ; chemistry

Objective To investigate the effects of duration of surgery on flash-induced visual evoked potentials (VEP) in patients undergoing spinal surgery in prone position.Methods Eighty-two ASA Ⅰ or Ⅱ patients of both sexes aged 20-76 yr weighing 43-96 kg undergoing spinal surgery in prone position were divided into 3 groups according to the duration of surgery:group S≤2 h ( n =34) ; group M 2-4 h ( n =38) and group L≥4 h ( n =10).VEP was monitored using protektor VEP monitoring device (Xltek Co.,Canada).The latency,amplitude and recovery time of wave P100 were recorded before and 10 min after induction of anesthesia and at the end of surgery.Results Compared with group S,the amplitude of wave P1000 was significantly decreased at the end of surgery in group M,the lantency of wave P100 was significantly prolonged,while the amplitude of wave P100 was decreased at the end of surgery in group L ( P ＜ 0.05).Compared with group M,the lantency of wave P100 was significantly prolonged,while the amplitude of wave P100 was decreased at the end of surgery in group L ( P ＜ 0.05).Compared with groups S and M,the recovery time of wave P100 was significantly prolonged in group L ( P ＜0.05).There was no significant difference in the recovery time of wave P100 between groups S and M ( P ＞ 0.05).Conclusion Duration of surgery (≥4 h) can affect flash-induced VEP,the longer the duration,the stronger the effects.

Objective To investigate the relationship between plasma tau protein, phosphorylated tau protein (p-tau) protein and cognitive function in subjects with generalized brain atrophy. Methods A total of 100 subjects with moderate and severe brain atrophy were divided into two groups according to cognitive function: normal group (n=50 cases) and dementia group (n=50 cases). And their gender, age, educational level, etc. are recorded. The tau protein and p-tau protein content in plasma were measured by double antibody sandwich enzyme-linked immunosorbent assay (ELISA). The differences between plasm tau and p-tau protein expression and their relationship with cognitive function were analyzed. Results Plasma tau protein and p-tau protein levels were significantly higher (P<0.05) in the dementia group [(210.92±43.79)pg/mL、(81.15±16.85)pg/mL] than in the normal group[(210.92±43.79)pg/mL、(81.15±16.85)pg/mL]. Plasma tau protein and p-tau protein levels were negatively correlated with the MMSE score (P<0.05) and had no significant correlation with the degree of brain atrophy (P>0.05). Conclusion Cognitive impairment may be associated with elevated tau protein levels in patients with extensive brain atrophy.

Objective:To investigate the effects of poly adenosine diphosphate ribose polymerase-1(PARP-1) inhibitor fluzoparib on proliferation, apoptosis and migration of pancreatic cancer PANC1 cells.Methods:PANC1 cells cultured in conventional culture medium were used as control group, and PANC1 cells cultured in the medium containing fluzoparib were used as fluzoparib group. The effects of fluzoparib with different concentrations on the proliferation of PANC1 cells were detected by CCK8 method, and the half inhibitory concentration (IC 50) of fluzoparib on PANC1 cells was calculated. The effect of fluzoparib on apoptosis and cell cycle of PANC1 cells was detected by flow cytometry, and the migration ability of PANC1 cells was detected by cell scratch test and Transwell chamber. Results:Compared with control group, with the increase of fluzoparib concentration and the prolongation of the action time, the cell proliferation activity of PANC1 in fluzoparib group was significantly decreased, and the differences were statistically significant (all P values <0.05). IC 50 of fluzoparib on PANC1 cells cultured for 24 h was 0.03 mmol/L. After 24 h culture, the IC 50 apoptosis rate of fluzoparib group was (32.19±2.48)%, and the apoptosis rate of control group was (21.99±6.30)%. The former was greatly higher than the latter, and the difference was statistically significant ( P<0.05). The proportion of cells in G 2/M phase was (16.28±0.62)% in the fluzoparib group and (11.64±0.88)% in the control group, and the difference between the two groups was statistically significant ( P<0.05). The migration rates of PANC1 cells in IC 50 fluzoparib group in 12 h and 24 h culture were (2.59±1.46)% and (19.76±7.84)%; and those in control group were (27.08±2.17)% and (45.92±3.61)%, respectively. The number of transmembrane cells was (348±19) cells/10 visual field in the fluzoparib group and (587±14) cells/10 visual field in the control group. The migration ability of PANC1 cells in fluzoparib group was significantly lower than that in control group ( P<0.05). Conclusions:Fluzoparib can inhibit the proliferation and migration of PANC1 cells and promote the apoptosis of PANC1 in vitro, which may be an effective drug for the treatment of pancreatic cancer.

OBJECTIVETo study the severe acute respiratory syndrome (SARS)-associated coronavirus genotype and its characteristics.

METHODSA SARS-associated coronavirus isolate named ZJ01 was obtained from throat swab samples taken from a patient in Hangzhou, Zhejing province. The complete genome sequence of ZJ01 consisted of 29,715 bp (GenBank accession: AY297028, version: gi: 30910859). Seventeen SARS-associated coronavirus genome sequences in GenBank were compared to analyze the common sequence variations and the probability of co-occurrence of multiple polymorphisms or mutations. Phylogenetic analysis of those sequences was done.

RESULTSBy bioinformatics processing and analysis, the 5 loci nucleotides at ZJ01 genome were found being T, T, G, T and T, respectively. Compared with other SARS-associated coronavirus genomes in the GenBank database, an A/G mutation was detected besides the other 4 mutation loci (C:G:C:C/T:T:T:T) involved in this genetic signature. Therefore a new definition was put forward according to the 5 mutation loci. SARS-associated coronavirus strains would be grouped into two genotypes (C:G:A:C:C/T:T:G:T:T), and abbreviated as SARS coronavirus C genotype and T genotype. On the basis of this new definition, the ZJ01 isolate belongs to SARS-associated coronavirus T genotype, first discovered and reported in mainland China. Phylogenetic analysis of the spike protein gene fragments of these SARS-associated coronavirus strains showed that the GZ01 isolate was phylogenetically distinct from other isolates, and compared with groups F1 and F2 of the T genotype, the isolates of BJ01 and CUHK-W1 were more closely related to the GZ01 isolate. It was interesting to find that two (A/G and C/T) of the five mutation loci occurred in the spike protein gene, which caused changes of Asp to Gly and Thr to Ile in the protein, respectively.

CONCLUSIONAttention should be paid to whether these genotype and mutation patterns are related to the virus's biological activities,epidemic characteristics and host clinical symptoms.

Objective:To analyze the risk factors of fatal outcome in patients with severe COVID-19.Methods:The clinical characteristics of 107 patients with severe COVID-19 admitted in Renmin Hospital of Wuhan University from February 12 to March 12, 2020 were retrospectively analyzed. During the hospitalization 49 patients died (fatal group) and 58 patients survived (survival group). The clinical characteristics, baseline laboratory findings were analyzed using R and Python statistical software. The risk factors of fatal outcome in patients with severe COVID-19 were analyzed with multivariate logistic regression.Results:Univariate analysis showed that the two groups had statistically significant differences in age, clinical classification, dry cough, dyspnea and laboratory test indicators ( P<0.05 or <0.01). The random forest model was used to rank the significance of the statistically significant variables in the univariate analysis, and the selected variables were included in the binary logistic regression model. After stepwise regression analysis, the patient’s clinical type, age, neutrophil count, and the proportion of CD3 cells are independent risk factors for death in severe COVID-19 patients. Dry cough is an independent protective factor for the death of severe COVID-19 patients. Conclusion:COVID-19 patients with fatal outcome are more likely to have suppressed immune function, secondary infection and inflammatory factor storm. These factors may work together in severe patients, leading to intractable hypoxemia and multiple organ dysfunction and resulting in fatal outcome of patients. The study indicates that timely intervention and treatment measures against above factors may be effective to save the lives of patients with severe COVID-19.