Objective To observe three-dimensional structure and biological features of rat acellular spinal cord scaffold prepared by sonic oscillation and chemical extraction in order to offer an ideal scaffold for spinal cord tissue engineering research.Methods Rat spinal cord underwent acellular treatment with sonic oscillation and chemical extraction (Triton X-100 at volume fracture of 2％ and sodium deoxycholate at volume fracture of 2％) (acellular spinal cord group).In contrast with spinal cord tissue of normal rats (control group),general morphology,histology and ultramicro three-dimensional structure of acellular spinal cord scaffold were observed and aperture size,factor of porosity,water ratio,enzymolysis ratio and stability in water solution of the scaffold were also detected.Results Acellular spinal cord group showed effective removal of original cell components with factor of porosity for (94.57 ±3.45) ％ and water content for (88.62 ± 1.0) ％,and satisfactory three-dimensional structure with average aperture of 46 μm.Scaffold showed gradual degradation in enzymolysis solution and enzymolysis rate reached (69.03 ± 2.19)％ at 20 hours.Besides,scaffold showed stepwise disintegration in double distilled water and hydrolysis rate was (62.55 ± 1.70) ％ at 8 days.While,normal spinal cord showed close structure,generous neurons and myelin sheath with factor of porosity for (0.04 ± 0.02) ％ and water content for (62.4 ± 1.5) ％,and unobvious pore structure under scanning electron microscope.Normal spinal cord were degraded gradually in enzymolysis solution and enzymolysis rate was (37.62 ± 0.9)％ at 20hours.In the meantime,normal spinal cord were disintegrated gradually in double distilled water and hydrolysis rate was (40.97 ± 0.81) ％ at 8 days.Conclusions Acellular spinal cord scaffold prepared by sonic oscillation plus chemical extraction achieves complete removal of cell components,intact extracellular matrix,and satisfactory results in three-dimensional network structures,factor of porosity and water content.Also,the scaffold meets theoretical demands of tissue-engineered spinal cord scaffold and is an ideal alterative for tissue-engineered spinal cord scaffold.

BACKGROUND:There is no effective drug for idiopathic pulmonary fibrosis (IPF), because of a lack of the animal model imitating the complete pathogenesis of human IPF. Therefore, it is critical to establish an ideal animal IPF model used for investigating the underlying pathogenesis and developing a kind of effective drug. OBJECTIVE:To establish an animal model that can mimic more characters of human IPF. METHODS:Seventy male C57BL/6 mice were randomly divided into two groups, fol owed by subjected to the intraperitoneal injection of bleomycin (35 mg/kg) on days 1, 4, 8, 11, 15, 18, 22, and 25, twice (group A) or once (group B) a week. Mice were sacrificed at 2, 4, 6, 8, and 10 weeks after the eighth injection, and the lung tissues were moved used for hematoxylin-eosin, Masson and immunohistochemical stainings. RESULTS AND CONCLUSION:There were various degrees of alveolitis and pulmonary fibrosis in the two groups at different time points after the last injection. The scores of alveolitis and pulmonary fibrosis in the group A began to gradual y increase from the 2nd week and reached the highest level at the 6th-8th weeks until the 10th week. In contrast, the scores of alveolitis and pulmonary fibrosis in the group B peaked at the 2nd week, then fluctuately decreased, and were significantly lower than those in the group A at the 6th week (P<0.05). Immunohistochemistry showed that type I col agen deposition was mainly distributed in the subpleural region, peri-vascular region and alveolar septa, which was consistent with Masson staining findings. The expression levels of transforming growth factorβ1 (TGF-β1) andα-smooth muscle actin (α-SMA) in the regions developing alveolitis and pulmonary fibrosis were significantly increased. In the group A, the expression levels of type I col agen, TGF-β1,α-SMA, and the hydroxyproline content in the lung tissues reached the peak level at 6-8 weeks. However, in the group B, al above indicators reached the highest level at the 2nd week, but gradual y decreased thereafter. At the 4th week, the expression Levels of TGF-β1 andα-SMA in the group B were significantly lower than those in the group A (P<0.05). At the 6th week, the hydroxyproline and type I col agen levels in the group B were significantly lower than those in the group A (P<0.05). In conclusion, the mouse model of pulmonary fibrosis induced by intraperitoneal injection of 35 mg/kg bleomycin twice weekly can be used to mimic the repetitive wound healing process, pathological morphology and cytokine changes of human IPF, which is prone to administration, with better stability and repeatability. This model is of great significance for the study on IPF. Subject headings:Disease Models, Animal;Pulmonary Fibrosis;Bleomycin

Objective To construct genipin-crosslinked rat acellular spinal cord scaffolds and evaluate their enzymatic degradation rate,biomechanical properties and cytotoxicity.Methods Rat spinal cord scaffolds were decellularized by chemical extraction and chemically crosslinked with 5 g/L genipin solution.Micro-structure of the uncrosslinked and genipin-crosslinked acellular spinal cord scaffolds were observed by HE staining and scanning electron microscopy and properties of pore size,porosity,water ratio,and degradation rate in 2.5 g/L trypsin enzyme solution were examined.Ultimate tensile strength and elastic modulus of normal rat thoracic spinal cord,uncrosslinked and genipin-crosslinked acellular spinal cord scaffolds were determined on Instron mechanical testing instrument.Rat bone marrow mesenchymal stem cells were cultured in lixivium of uncrosslinked and genipin-crosslinked acellular spinal cord scaffolds and MTT assay for relative cell growth rate was test to evaluate the cytotoxicity of scaffolds.Results The uncrosslinked and the genipin-crosslinked acellular spinal cord scaffolds possessed a similar three-dimensional mesh-porous structure with a mean pore diameter about 30 μm and a porosity over 80％,but there was a statistical difference between the two groups(P ＞ 0.05).Water ratio of genipincrosslinked scaffolds was (229.7 ± 12.5) ％,far lower than (283.4 ± 11.2) ％ of uncrosslinked scaffolds (P ＜ O.05) ; genipin-crosslinked acellular spinal cord scaffolds had lower weight loss at each time point than the uncrosslinked acellular spinal cord scaffolds (P ＜ 0.05),but the stability in trypsin,ultimate tensile strength and elastic modulus of acellular spinal cord scaffolds were significantly enhanced by genipin-crosslinking (P ＜ 0.05).Furthermore,no obvious cytotoxicity was observed in the uncroslinked and genipin-crosslinked scaffolds.Conclusions Rat acellular spinal cord scaffolds present no obvious change in structure after genipin-crosslinking,but there is significant improvement in the biomechanical properties and ability against enzymatic degradation and no marked cytotoxicity.Hence,the genipincrosslinked scaffolds are promising in tissue engineering for spinal injury.

Objective To investigate the regeneration and differentiation of HOCs in the 2-AAF/PHx rat models. To explore the expression of Cyr61and its mechanism in differentiation of HOCs in vitro. Methods In 2-AAF/PHx rats model,induction and expansion of HOCs were detected by immunochemistry and HE staining. West-ern blot was used for observing the expression of Cyr61. Furthermore,the expression of Cyr61 andβ-catenin were detected by Western blot in differentiation of WB-F344 cells in vitro. Results Cyr61 protein level increased as a re-sult of HOCs in rats livers after 2-AAF/PHx. In addition,the expression of Cyr61 and β-catenin significantly in-creased during WB-F344 cells differentiation in vitro. Conclusions Cyr61 might play an important role as a signal-ing mediator in HOCs response and closely correlate with Cyr61 andβ-catenin in proliferation and differentiation of HOCs.

Objective To investigate the degradation of dicalcium phosphate dehydrate-coated Mg-Zn alloy in vivo and bone formation. Methods Left femoral condyles were drilled in 72 New Zealand rabbits, and were randomly divided into experiment group (n＝24, implanted with dicalcium phosphate dehydrate-coated Mg-Zn alloy rods), Mg-Zn alloy control group (n＝24, implanted with Mg-Zn alloy rods) and poly-L-lactide acid rod group (n＝24, implanted with poly-L-lactide acid rods). Serum concentrations of Mg~(2+) were examined 1 d pre-operation, and 1 d, 1 week, 2 weeks, 5 weeks and 10 weeks post-operation in experiment group and Mg-Zn alloy control group. Operation sites were examined by X-rays at 3, 6, 12 and 18 weeks post-operation. After X-ray examination at each time point, 6 rabbits in each group were sacrificed, and subjected to histopathological observation of live and kidney tissues by HE staining. Tissues from condyles of femur were observed by HE staining and 2, 4, 6-trinitrophenol rosein staining, and mineral apposition rate of bone was calculated. Results There was no significant difference in the concentrations of serum Mg~(2+) at each time point between Mg-Zn alloy control group and experiment group (P>0.05). X-ray examination revealed gas emerged near the implants 3 weeks after surgery in Mg-Zn alloy control group. However, there was no obvious histological abnormality in liver and kidney tissues. The mineral apposition rate was higher and the degradation of material was lower in experiment group than those in the other two groups. Conclusion Dicalcium phosphate dehydrate-coated Mg-Zn alloy has a favourable biocompatibility, and degrades more slowly in vivo.

BACKGROUND:A novel biodegradable Mg-Zn alloy has been designed,in which the density and the Young's modulus are proximal to human bone,at the same time,it depletes the toxicity of aluminium and rare earth element in commercial magnesium alloys.OBJECTIVE:To evaluate the cytocompatibility of biodegradable Mg-Zn alloy.DESIGN,TIME AND SETTING:Contrast study was performed in the central laboratory of the Sixth People's Hospital of Shanghai Jiao Tong University between November 2007 and March 2008.MATERIALS:The Mg-6wt%Zn was prepared by School of Materials Science and Engineering of Shanghai Jiao Tong University,with the density was 1.82 g/cm3 and the Young's modulus was 44 GPa.L-929 cells for cytocompatibility test were provided by Chinese Academy of Science Type Culture Collection.Ten male New Zealand rabbits were employed in the hemolysis test.METHODS:The Mg-Zn alloy extraction medium was prepared by serial dilutions with fresh medium to 10%,50% and 100%.The experiments were carried out in a 96-well tissue-culture plate.Simple DMEM culture solution was taken as negative controls,while DMEM culture solution supplemented with 0.64% phenol served as positive controls.MAIN OUTCOME MEASURES:Relative proliferation rate of L-929 cells was determined at 2,4 and 7 days with MTT assay.The cytotoxicity of Mg-Zn alloy was evaluated according to ISO 10993-5:1999.The L-929 cell morphology and growth at 2,4 and 7 days were determined under inverted microscope.Based on ISO 10993-4:2002,hemolysis in vitro was evaluated through measuring erythrocyte lysis and ferrohemoglobin freeing degree with indirect contact method.RESULTS:The number of L-929 cells increased significantly and the morphology was not changed.The growth and morphology of cells in different Mg-Zn extraction medium had no difference from negative control group.Cytotoxicity test showed that biodegradable Mg-Zn alloy did not have obvious toxicity on L-929 cells,and the cytotoxicity of these extracts was in grade 0-1.Hemolysis test suggested that the Mg-Zn alloys did not have obvious hemolysis reaction,and the hemolysis index was 3.4%,which was less than the national standard (5%).CONCLUSION:The Mg-Zn alloys do not have obvious cytotoxicity and hemolysis reaction,which demonstrate that Mg-Zn alloys have good cytocompatibility.

We studied the effects of simulated microgravity on mouse oocytes maturation, and analyzed whether the tail-suspended model can be applied to investigate simulated microgravity effects on reproductive processes in female mice. Mouse oocytes were cultured in vitro with microgravity simulated by a rotating wall vessel bioreactor and by tail-suspended model, and the maturation rate of the mouse oocytes in the two models were examined in vivo. The maturation rate of mouse oocytes cultured in simulated microgravity was 8.93%, and that was 72.33% in 1g gravity. In ratio, oocyte maturation rate had no significant difference between the rotational group and control group. Microgravity simulated by the tail-suspended model inhibited mouse oocytes maturation and increased the rate of oocytes abnormity. The maturation rate of tail-suspended mouse oocytes was 14.54%, which was significantly lower than that of control group. Tail-suspended model should be an ideal model to investigate simulated microgravity effects on reproductive processes of female mice.
Animals ; Cells, Cultured ; Female ; Hindlimb Suspension ; Mice ; Oocytes ; cytology ; physiology ; Oogenesis ; physiology ; Weightlessness Simulation

BACKGROUNDTo investigate the clinical characteristics of thoracic lymph node metastasis in lung cancer.

METHODSThree hundred and eighteen patients with lung cancer underwent pneumonectomy or lobectomy and lymphadenectomy from Jan 2000 to Jan 2002.

RESULTSA total of 1534 groups of lymph nodes were removed. Metastatic frequency of thoracic lymph nodes was 58.5% (186/318), in which N1 was 27.0% (86/318), N2 was 31.4% (100/318). There were higher frequencies of lymph node metastasis in 4, 7, 10, 11 regions around the root of lung. Among the skipping N2 metastasis (14.5%, 46/318), upper lobe cancer led to only upper mediastinal lymph node metastasis, however, lower or right middle lobe cancer caused both upper and lower mediastinal lymph node metastasis. Of the patients with swelling hilar and mediastinal lymph nodes reported by preoperative CT scan, only 48.2% were confirmed with lymph node metastasis by postoperative histopathology; while 22.4% of the patients with normal size lymph nodes had lymph node metastasis.

CONCLUSIONSIf there is no hilar and inferior carinal metastatic lymph node in patients with upper lobe cancer, the lower mediastinal lymph node dissection might not be necessary. But systematic mediastinal lymph node dissection should be performed in patients with lower lobe or right middle lobe cancer whether there is hilar or inferior carinal metastatic lymph node or not. The extent of lymph node dissection should not depend on the results of preoperative chest CT scan.

Objective:To investigate the mechanism of bladder cancer treatment by using Scutellaria barbata and Codonopsis pilosula drug pair through network pharmacology. Methods:The drug composition of the drug pair was screened using TCMSP, and their action targets were predicted using Swiss Target Prediction. GeneCards was used to obtain disease targets of bladder cancer, and venny 2.1 was used to obtain intersection targets. PPI analysis was performed using STRING, and a network diagram was constructed using Cytoscape. GO and KEGG analysis were conducted using Metascape. A drug-target-pathway network map was constructed using Cytoscape software. Nude mice were randomly divided into a model group and a treatment group to establish a bladder cancer mouse model. On the 8th day after model formation, the mice in the model group were administered intragastrically with a dose of 342.86 mg/kg, 0.2 ml, twice/day. On the 28th day after modeling, the tumor size of nude mice was measured. Prostaglandin G/H Synthetase 2 (PTGS2), PTGS1, Nuclear Receptor Coactivator 2 (NCOA2), Retinoic Acid X Receptor α (RXRA), Progesterone Receptor (PGR), Mitogen-Activated Protein Kinase 1 (MAPK1), Reticuloendothelial Proliferation virus oncogene homology A (RELA), and Akt1 levels were detected by enzyme-linked immunosorbent assay.Results:The results show that 45 active components of the drug pair directly acted on 187 disease targets through multiple pathways to treat bladder cancer, in which Quercetin, luteolin, wogonin, 7-Methoxy-2-methyl isoflavone, baicalein, beta-sitosterol, Stigmastero, and other core ingredients, as well as PTGS2, PTGS1, NCOA2, RXRA, PGR, MAPK1, RELA, and Akt1 are critical targets. The results of gene function annotation analysis show that the biological processes most likely related to crossover genes mainly involved responses to hormones, cell responses to lipids, responses to foreign stimuli, and responses to bacterial molecules. The cell components mainly involves transcription regulatory complexes, membrane rafts, membrane microregions, and RNA polymerase Ⅱ transcriptional regulatory complexes, etc. The molecular functions mainly involve transcription factor binding, DNA-binding transcription factor binding, RNA polymerase Ⅱ specific DNA-binding transcription factor binding, nuclear receptor activity, ligand-activated transcription factor activity, etc. The results of pathway enrichment analysis suggests that the main signaling pathways are AGE-RAGE, IL-17, PI3K-Akt, TNF, MAPK, HIF-1, apoptosis, p53, toll-like receptor, etc. Animal experiments show that the Scutellaria barbata and Codonopsis pilosula drug pair can significantly improve tumor size and also improve the expression levels of PTGS2, PTGS1, NCOA2, RXRA, PGR, MAPK1, RELA, and Akt1. Conclusions:The Scutellaria barbata and Codonopsis pilosula drug pair can regulate PTGS2, PTGS1, NCOA2, RXRA, PGR, MAPK1, RELA, and Akt1 and other diseases mainly through the regulation of AGE-RAGE, IL-17, PI3K-Akt, TNF, MAPK, HIF-1, apoptosis, p53, toll-like receptor, and other signaling pathways. Targeting enzyme activity and cell apoptosis can treat bladder cancer by regulating these biological processes.

Objective: To explore the humanistic caring ability, and to analyze the relationship between the positive psychological qualities, emotional intelligence and humanistic caring ability among the nursing interns, and provide theoretical basis to improve nursing students’ humanistic caring ability. Methods: A total of 132 nursing interns from a three Level of first-class hospital in Liaoning province, were investigated by using the general questionnaire, caring ability inventory, emotional intelligence scale and Positive Mental Characters Scale for China normal university. Results: The score of humanistic caring ability was (180.74±18.75). Among them, the average score of cognitive was the highest (73.71±10.93) and the average score of courage was the lowest (48.43±11.91). Emotional intelligence and positive psychological qualities were positively correlated with the humanistic caring ability, and positive psychological qualities was a intermediate variable between emotional intelligence and humanistic caring ability, and the mediating effect size is 18.71%. Conclusion The level of humanistic caring ability in nursing interns is lower, which needs to be further improved. The emotional intelligence and positive psychological qualities have a significant positive effect on the humanistic caring ability. Schools and internship hospitals can improve their sense of humanistic caring ability by developing the emotional intelligence and positive psychological qualities to stabilize the development of nursing career.