BACKGROUND:In the treatment of skin trauma with active repair,tissue engineering techniques are needed to generate new tissue to replace necrotic tissue.Skin scaffolds have a good application prospect in the field of wound repair.Skin scaffolds need to present three-dimensional porous structures with certain mechanical strength to meet the needs of cell proliferation and division.However,the mechanical strength of the currently used gelatin-based biomaterials is weak and cannot meet the requirements of the use of skin scaffolds. OBJECTIVE:To study the 3D printing process used in the preparation of tissue engineering skin scaffolds by gelatin/oxidized nanocellulose composites,and focus on the relationship between the porosity and mechanical strength of the scaffolds prepared under different process parameters. METHODS:Oxidized nanocellulose whiskers at 10%concentration were extracted from Humulus scandens and then compounded with 5%gelatin to obtain gelatin/oxidized nanocellulose composites.The elastic modulus of gelatin and gelatin/oxidized nanocellulose composite was determined.Skin scaffolds were prepared by 3D printing extrusion molding using gelatin/oxidized nanocellulose composite as the base material.Mechanical and rheological properties of the composite were tested to determine extrusion molding parameters(filling gap 1.5-2.5 mm,uniform distribution of 0.1 mm;air pressure of 160-200 kPa),and the skin scaffold with a three-dimensional porous structure was prepared.The compressive performance of the skin scaffold was tested and compared with the finite element analysis results.The relationship between the filling gap and the porosity and mechanical strength of the scaffold was demonstrated. RESULTS AND CONCLUSION:(1)The elastic modulus of 5%gelatin was increased by 8.84 times by adding 10%oxidized nanocellulose whisker.A gel filament with a diameter of 1 mm was obtained by extrusion at the air pressure of 160 kPa.When the filling gap increased from 1.5 mm to 2.5 mm,the theoretical porosity of the scaffold increased from 33%to 60%,but the compressive strength decreased from 230 000 Pa to 95 000 Pa.(2)These findings showed that the skin scaffold with theoretical porosity of 50%and elastic modulus of 160 000 Pa was prepared by using 2 mm filling gap.The scaffold had a clear three-dimensional porous structure.

Objective: To study the protective effect of Ascorbic acid (AA) on the injury of nickel-exposed mouse embryonic fibroblasts (NIH/3T3) . Methods: A model of damage induced by 50 μg/mL nickel refining dust was established to determine the relative survival rate of cells, superoxide dismutase (SOD) , lactate dehydrogenase (LDH) and glutathione peroxidase. (GSH-Px) activity, hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) content, and p53 (wild-type) , Bcl-2 protein expression. To investigate the protective effect of different doses of ascorbic acid (25, 50, 100 mmol/L) on nickel-refined dust-induced NIH/3T3 cell injury. Results: The study showed that ascorbic acid Ⅲ group can make the NIH/3T3 cell survival rate increased significantly; Apoptosis rate was reduced; The vitality of SOD and GSH-Px increased significantly, and the difference was statistically significant (P<0.05) . At the same time, the level of MDA and H₂O₂ and the activity of extracellular LDH enzyme were significantly reduced, and the difference was statistically significant (P<0.05) . The results showed that nickel refining dust induced cell damage through up-regulation of p53 protein and down-regulation of Bcl-2 protein expression; ascorbic acid interventions, the expression level of Bcl-2 protein in ascorbic acid II and III groups was higher than that of nickel refining dust group, and the difference was statistically significant (P<0.05); The expression level of p53 protein in each dose group of ascorbic acid was lower than that of nickel refined dust group, and the difference was statistically significant (P<0.05). Conclusion With the increase of concentration of ascorbic acid, oxidative damage levels, antioxidant enzyme levels, reduce cell apoptosis, reduce expression of p53, increased expression of Bcl-2. It showed that ascorbic acid had protective effect on NIH/3T3 cell injury induced by nickel refining dust.

This study was aimed to verify the hypothesis that Ge-Xia Zhu-Yu (GXZY) decoction protects liver from porcine serum-induced oxidative stress through the thioredoxin system.SD rats were randomly divided into the blank control group,model group,normal rat + GXZY decoction group,model rat + GXZY group.The rat autoimmune hepatic fibrosis model was induced with porcine serum by intraperitoneal injection (0.5 mL/each rat) twice a week.And GXZY decoction (7.37 g raw material/kg· d) was simultaneously administered daily by gavage.Lipid peroxidation (LPO) levels and thioredoxin reductase (TrxR) activity in liver tissues were determined by the colorimetric method.Polymerase chain reaction (PCR) was used to analyze the transcription factor nuclear factor erythroid 2-related factor 2 (Nfe2l2,previously known as Nrf2) mRNA expression.And the western blot was used to analyze the thioredoxin-1 (Trx1) protein expression and Akt phosphorylation in the liver.The results showed that compared to the model control group,the GXZY decoction group attenuated porcine serum-induced oxidative stress,as indicated by the LPO level,in liver tissues.Furthermore,GXZY decoction significantly enhanced TrxR activity,Trx1 protein expression,Nfe2l2 mRNA expression,and Akt phosphorylation (all P＜0.05).It was concluded that the strong antioxidant properties of GXZY decoction in the porcine serum rat model was due to the enhancement of the hepatic thioredoxin system via activating Akt-Nrf2 signaling pathway.The study results provided experimental evidences for the supporting of this hypothesis.

A method for simultaneous determination of PCDDs, dl-PCBs, BFRs and PBDD/Fs in flue gas from stationary source was developed. The sample was extracted by Soxhlet apparatus with toluene, and followed by purification through sulfuric acid partition and multi-layer silica gel column separation. The target compounds were then all separated by passing through the active carbon-dispersed silica gel column and reversal eluting. Gas chromatography coupled with a thermostable capillary column ( short length, thin stationary phase film) was operated at pulse injection mode. High resolution mass spectrometry set at low-electron-energy ionization was used for quantification. The high- and low-brominated compounds were determined simultaneously. The detection limits of this method were 0. 081-1. 2 pg for PCDD/Fs, 0. 10-0. 32 pg for dl-PCBs, 0. 14-12 pg for PBDEs, 0. 26-16 pg for new BFRs, 0. 44-3. 6 pg for tetra- to hepta-BDD/Fs and 8. 2-12 pg for OBDD/F. Recoveries ( RSDs) in spiked flue gas samples were 88%-115%(2. 9%-6. 1%) for PCDD/Fs, 84%-118% (3. 2%-10%) for dl-PCBs, 71%-135% (2. 1%-18%) for PBDEs, 71%-114% (2. 9%-7. 4%) for new BFRs, 83%-127% (5. 2%-10%) for tetra-to hepta-BDD/Fs and 52%-149% ( 23%-24%) for OBDD/F. All quality control data fell within the acceptable range specified in analysis standards for flue gas.

OBJECTIVETo study biological effect of recombinant human erythropoietin (RhEPO) on the expression of oligodendrocyte in the neuron glia antigen 2(NG2), Nogo receptor-interacting protein 1(LINGO-1), myelin basic protein (MBP) and myelin associated glycoprotein (MAG), and to explore the protective mechanism of RhEPO for oligodendrocyte after cerebral infarction.

METHODSExperimental rats were randomly divided into the treatment group (RhEPO at a dose of 3 000 U/kg) or saline control group. Both groups received intraperitoneal injection of RhEPO after cerebral ischemia in 30 min, 3 h, 6 h, 12 h and 24 h, which was administered daily for 7 days. The modified neurological severity score (mNSS) and histology were analyzed, and immunohistochemistry was used to detect the protein expression of NG2, MAG, MBP and LINGO-1.

RESULTSThe overall mNSS of RhEPO treatment group significantly decreased compared with the saline control group on the seventh day after cerebral infarction (P<0.05). Such treatment effect was more obvious in the treatment group at 30 min and 3 h (P<0.01). Compared with the saline control group, the numbers of NG2 positive cells increased in RhEPO treatment group. In contrast, the expression of LINGO-1 protein significantly decreased (P<0.05), with a dramatic decrease observed at 30 min and 3 h (P<0.01). However, the expression of MBP protein decreased more significantly in saline control group, while the level of the MAG protein expression increased. The differences were statistically significant (P<0.05), especially at 30 min (P<0.01).

CONCLUSIONSAfter cerebral ischemia, RhEPO promotes the proliferation of NG2 positive cells, and inhibits the expression of LINGO-1 and MAG proteins. RhEPO improves the proliferation and differentiation of oligodendrocyte precursor cells, which in turn protects neuronal function, particularly at the early phase of ischemia.

OBJECTIVETo observe the clinical efficacy and safety on moderate and severe persistent allergic rhinitis treated with acupuncture.

METHODSSixty-six patients of moderate and severe persistent allergic rhinitis were randomized into an acupuncture group (34 cases) and a western medication group (32 cases). In the acupuncture, group, acupuncture was applied to Dazhui (GV 14), Feishu (BL 13), Pishu (BL 20), Ganshu (BL 18) and Shenshu (BL 23) in the prone, retained for 20 min; then in the supine, at Baihui (GV 20), Yintang (GV 29), yingxiang (LI20) Taichong (LR 3) and Hegu (LI 4), retained for 20 min. Acupuncture was given once every two days, three times a week, continuously for 8 weeks. In the western medication group, cetirizine hydrochloride was taken orally, 10 mg each time, once every day, continuously for 8 weeks. Separately, before treatment, after the treatment of 1 and 2 months and in 1 month after treatment, the total nasal symptom score (TNSS), the scores in the emotion rating scale for Ganzangxiang of TCM (ERSG) and the rhinoconjunctivitis quality of life questionnaire (RQLQ) were observed in the patients of the two groups. The clinical efficacy was compared between the two groups.

RESULTS(1) For TNSS, the results after 1 and 2 months treatment and in 1 month after treatment were all, reduced as compare with that before treatment separately in the two groups (P < 0.05, P < 0.01) The result after 2 months treatment was lower than that after 1 month treatment in the acupuncture group (P < 0.05). In 1 month after treatment, the result in the acupuncture group was lower than that in the western medication group (P < 0.05). (2) For ERSG, the score after 2 months treatment was lower than that before treatment in the two groups (both P < 0.05). The score after 2 months treatment in the acupuncture group was lower than that in the western medication group (P < 0.05). (3) For RQLQ, the score after 1 month treatment was lower than that before treatment and the score after 2 months treatment was lower than that after 1 month treatment in the two groups (all P < 0.05). The score after 1 and 2 months treatment and in 1 month after treatment in the acupuncture group was lower than that in the western medication group separately (all P < 0.05). (4) The total effective rate was 91.2% (31/34) in the acupuncture group and was 90.6% (29/32) in the western medication group, without significant difference between the two groups (P > 0.05).

CONCLUSIONAcupuncture is the safe and effective intervention on moderate and severe persistent allergic rhinitis. Compared with the western medicine group, the efficacy in the acupuncture group presents much more advantageous at its durability.

Acupuncture Points ; Acupuncture Therapy ; Adult ; Female ; Humans ; Male ; Middle Aged ; Quality of Life ; Rhinitis, Allergic ; diagnosis ; therapy ; Young Adult

Objective To investigate the association between expression of the epithelial?to?mesenchymal transition(EMT)biomarkers and the malignant progression of gastric cancer in primary tumors and metastases and their possible correlation with progression of gastric cancer(GC). Methods The EMT biomarkers including E?cadherin,β?catenin,N?cadherin,Snail and TGF?β1 were detected by immunohistochemical method for 145 cases of gastric cancer(GC),25 cases of abnormal hyperplasia,13 cases of intestinal metaplasia,42 cases of lymph node metastasis and 40 cases of normal gastric mucosa tissues. Results Positive rates of TGF?β1,Snail,E?cadherin,β?catenin and N?cadherin were 73.5%,65.5%, 14.5%,53.1%and 35.9%,respectively,in gastric cancer tissues and 100%,100%,0%,27.5%and 2.5%,respectively,in normal gastric tissues, with a significant difference between the two groups(P<0.05). The decreased expression of E?cadherin andβ?catenin and the increased expression of TGF?β1 were related to the depth of invasion of gastric cancer(P<0.05). The expression of E?cadherin was correlated positively with the expres?sion ofβ?catenin,but negatively with the expression of TGF?β1. Whereas,the expression of N?cadherin was correlated positively with the expression of TGF?β1(P<0.05). The expression of E?cadherin andβ?catenin in lymph node metastasis was significantly higher than that in gastric cancer tis?sues,while the expression of TGF?β1 was lower than in gastric cancer tissues(P<0.05). Conclusion The increased expression of TGF?β1 and Snail and the decreased expression of E?cadherin,β?catenin,and N?cadherin are involved in the processes of invasion and metastasis of GC. The transformation of E?cadherin to N?cadherin and the expression of TGF?β1 may play an important role in the development of GC. In lymph node me?tastasis,the phenomenon of mesenchymal?to?epithelial transition(MET)occurs.

Objective To study biological effect of recombinant human erythropoietin ( RhEPO) on the expression of oligodendrocyte in the neuron glia antigen 2 ( NG2 ) , Nogo receptor-interacting protein 1 (LINGO-1), myelin basic protein (MBP) and myelin associated glycoprotein (MAG), and to explore the protective mechanism of RhEPO for oligodendrocyte after cerebral infarction.Methods Experimental rats were randomly divided into the treatment group ( RhEPO at a dose of 3 000 U/kg) or saline control group.Both groups received intraperitoneal injection of RhEPO after cerebral ischemia in 30 min, 3 h, 6 h, 12 h and 24 h, which was administered daily for 7 days.The modified neurological severity score ( mNSS) and histology were analyzed, and immunohistochemistry was used to detect the protein expression of NG2, MAG, MBP and LINGO-1.Results The overall mNSS of RhEPO treatment group significantly decreased compared with the saline control group on the seventh day after cerebral infarction ( P<0.05 ).Such treatment effect was more obvious in the treatment group at 30 min and 3 h ( P<0.01).Compared with the saline control group, the numbers of NG2 positive cells increased in RhEPO treatment group.In contrast, the expression of LINGO-1 protein significantly decreased (P<0.05), with a dramatic decrease observed at 30 min and 3 h ( P<0.01).However, the expression of MBP protein decreased more significantly in saline control group, while the level of the MAG protein expression increased.The differences were statistically significant ( P<0.05), especially at 30 min (P<0.01).Conclusions After cerebral ischemia, RhEPO promotes the proliferation of NG2 positive cells, and inhibits the expression of LINGO-1 and MAG proteins.RhEPO improves the proliferation and differentiation of oligodendrocyte precursor cells, which in turn protects neuronal function, particularly at the early phase of ischemia.

Objective To investigate the relevance between protein expression and methylation of MG-MT and hMSH2 in glioma patimts.Methods Immunohistochemical and methylation specific PCR were adopted respectively to test on 275 cases of glioma patients for the protein expression and methylation situation of MGMT and hMSH2.Results The negative protein expression rate of MGMT and hMSH 2 in the tissue of brain golima were 47.2% and 62.5% respectively;the occurrence of methylation in gene promoter region were accordingly 41.8% and 22.4%.Statistical analysis revealed that MGMT promoter methylation in peripheral blood gene groups was related with the protein negative expression of tumor tissue (P<0.05),while there was no relationship between the protein expression of hMSH2 and its gene promoter methylation(P>0.05).Conclusion The meth-ylation of MGMT is a common molecular situation in the generation of brain glioma ,which may be connected with that of tumor.However,hMSH2 promoter methylation might not the main reason for inactivation of hMSH 2 pro-tein,there may be other important factors affecting its expression .

OBJECTIVETo study the correlation between IDH1 mutation, MGMT expression, clinicopathologic features and post-radiotherapy prognosis in patients with astrocytoma.

METHODSDetection of IDH1 mutation and MGMT expression was carried out in 48 cases of astrocytoma (WHO grade II to III) by EnVision method with immunohistochemical staining. Follow-up data, including treatment response and overall survival time, were analyzed.

RESULTSThe rates of IDH1 mutation and MGMT expression in astrocytomas were 62.7% (30/48) and 47.9% (23/48), respectively. There was a negative correlation between IDH1 mutation and MGMT expression (r = -0.641, P < 0.01). The age of patients with IDH1 mutation was younger at disease onset. The IDH1 mutation rate in patients with WHO grade II astrocytoma was higher than that in patients with WHO grade III tumor (P < 0.05). The age at onset was an independent factor affecting the expression of mutant IDH1. After radiotherapy, patients with IDH1 mutation+/MGMT- tumor carried a longer overall survival time than patients with IDH1 mutation-/MGMT+ tumor (P < 0.05).

CONCLUSIONSThere is a correlation between IDH1 mutation and MGMT expression in WHO grade II to III astrocytoma. Age at onset is an independent factor affecting the expression of mutant IDH1. Tumors with IDH1+/MGMT- pattern show better response to radiotherapy than tumors with IDH1-/MGMT+ pattern. Detection of IDH1 mutation and MGMT protein expression can provide some guidance in choice of treatment modalities in patients with astrocytoma.

Adult ; Age Factors ; Age of Onset ; Aged ; Astrocytoma ; genetics ; metabolism ; mortality ; pathology ; radiotherapy ; Brain Neoplasms ; genetics ; metabolism ; mortality ; pathology ; radiotherapy ; DNA Modification Methylases ; metabolism ; DNA Repair Enzymes ; metabolism ; Female ; Humans ; Isocitrate Dehydrogenase ; genetics ; Male ; Middle Aged ; Mutant Proteins ; genetics ; Mutation ; Prognosis ; Tumor Suppressor Proteins ; metabolism