Objective To establish a CVS-11 pseudovirus particles ( pp)-based assay for detec-tion of neutralizing antibody against rabies virus. Methods An improved rapid fluorescence focus inhibition test ( RFFIT) for detection of neutralizing antibody against rabies virus ( RVNA) was established based on the CVS-11 pseudovirus expressing a luciferase reporter gene. Forty-six human serum samples were analyzed with the improved RFFIT and the results were compared with those by using standard RFFIT. Moreover, the improved RFFIT was used to detect the titers of RVNA in 91 serum samples collected from pet dogs and pet-breeders in Beijing. Results The coincidence rate of the improved RFFIT and the standard RFFIT was 100% regarding to the analysis of 46 human serum samples and 5 negative reference serum samples. Moreo-ver, the RVNA titers of all serum samples obtained with CVS-11 pseudovirus-based assay showed a signifi-cant high correlation with those obtained with standard RFFIT (n=46, r=0. 94, P<0. 000 1). All of the 91 serum samples collected from pet dogs and pet-breeders in Beijing were positive for RVNA as indicated by the improved RFFIT with a mean titer of 33. 01 IU/ml. Conclusion We established an improved RFFIT based on the CVS-11 pp expressing luciferase reporter gene, which might be used as a reliable alternative RFFIT for measuring RVNA titer. Analysis of the 91 serum samples collected in Beijing with the improved RFFIT showed that all samples were positive for RVNA.

Objective To construct novel 3-D composite bionic network and evaluate the histocompatibility . Meth?ods The novel 3-D composite bionic network was prepared from chitosan, hydroxyapatite, gelatin and pectin in certain ra?tio by biomimtic approach, which was co-cultured with MC3T3-E1. The cell compatibility was studied by using inverted phase contrast microscope, routine paraffin section staining, scanning electron microscopy and F-DA staining. The resultant scaffold material was implanted into the dorsal subcutaneous space of SD rats. The histocompatibility, blood vessel capabili?ties and the degradation of the material were observed 2, 4, 8 and 12 weeks after surgery. Results The structure of novel 3-D composite bionic network was three-dimensional and porous. The cells attached on scaffolds attached and grew well with polygonal or fusiform form. It was found that inflammatory reactions were alleviated gradually in the early stage . There was an increasing angiogenesis at late stage. Materials degraded and absorbed more slowly. Conclusion The present study sug?gests that the novel 3-D composite bionic network has good histocompatibility with easy vascularization, and will be a candi?date scaffold for bone tissue engineering.

ObjectiveTo explore the relationship between plasma A-FABP and obesity type and degree,glucose and lipid metabolism parameters and insulin sensitivity.MethodsPlasma adipocyte fatty acid binding protein (A-FABP) was detected by double antibody sandwich ELISA in fasting status in subjects with normal glucose regulation and normal weight (NW-NGR,n =44),overweight or obese subjects with normal glucose regulation (OB-NGR,n =36),newly-diagnosed type 2 diabetes mellitus (T2DM) and its subgroups of T2DM with normal weight ( NW-T2DM,n =89 ) and T2D)M with overweight or obesity (OB-T2DM,n =44).And glucose,lipids,insulin levels as well as anthropometrical parameters such as body mass index ( BMI ),fat content ( Fat％ ),waist circumference (WC) and waist hip ratio (WHR) were measured.Meanwhile insulin sensitivity was assessed by HOMA-IR.ResultsAfter age and sex adjustment,plasma A-FABP levels in OB-NGR,NW-T2DM,and OB-T2DM were significantly higher than that of NW-NGR [11.32(6.54 - 15.43)μg/L,14.60(10.35 -20.10) μg/L,18.25(12.85 -26.65) μg/L vs 9.32(3.72 - 14.00) μg/L,all P ＜0.05].There was no difference in plasma A-FABP levels between OB-NGR and NW-T2DM [ 11.32 (6.54 - 15.43 ) vs 14.60 ( 10.35 -20.10) μg/L,P ＞ 0.05 ],but the plasma A-FABP levels in OB-NGR and NW-T2DM were significantly lower than that of OB-T2DM [ 11.32(6.54 - 15.43) μg/L,14.60( 10.35 -20.10) μg/L vs 18.25( 12.85 -26.65 ) μg/L,P ＜0.01 ].In a multiple stepwise regression analysis,HOMA-IR,sex,WC and age were the most significant independent determinants for plasma A-FABP concentration (all P ＜ 0.05 ).Conclusions Plasma A-FABP is strongly associated with the abdominal obesity and insulin resistance,measurement of plasma A-FABP concentrations might be useful for diagnosis of abdominal obesity and type 2 diabetics.

BACKGROUND:Polyvinyl alcohol (PVA) hydrogel with similar porous structure and mechanical properties to the natural cartilage is very suitable for the repair of articular cartilage. However, the pure PVA hydrogel after lyophilization wil be accompanied by the shrinkage of the polymer network and the col apse of the pores, leading to the inhomogeneous performance of the material even in the state of re-swel ing. Addition of the active polymer wil increase the cel adhesion ability of PVA hydrogel. OBJECTIVE:To construct PVA/lota-carrageenan (l-CA) composite materials with different mass fractions of l-CA and evaluate the biocompatibility with vascular endothelial cel s. METHODS:PVA/l-CA composite films with different contents of l-CA were fabricated and then co-cultured with vascular endothelial cel s. Attachment, proliferation and morphological changes of vascular endothelial cel s on the composite were observed by scanning electron microscope and MTT assay to evaluate its biocompatibility. PVA/l-CA three-dimensional scaffold with different contents of l-CA were constructed, and hemolysis experiment was conducted according to the biological evaluation standards of medical devices, and the porosity and pore size were observed using scanning electron microscope. RESULTS AND CONCLUSION:In vitro experimental results showed that the addition of l-CA could significantly increase the biological activity of PVA hydrogel, and promote the cel attachment and proliferation on the scaffold. The hemolysis rate of each experimental group was less than 5%(the accepted safety standard), suggesting that the composite materials were in accordance with the standard of medical devices for hemolysis experiment. These findings indicate that the composite scaffolds with 20%-30%l-CA possess the pore size suitable for cel growth and proliferation and the porosity beneficial for transportation of nutrients and metabolites, which can serve as an excel ent scaffold for tissue engineering.

Objective To explore the effects of the new melatonin nonselective agonists Neu-P11 on intraocular pressure (IOP) and glial fibrillary acid protein (GFAP) expression in the retina of acute high IOP rat.Methods Twenty-four male Sprague-Dawley rats were randomly divided into 4 groups (6 cases in each group):Normal IOP with local treatment (NIL) group,high IOP with local treatment (HIL) group,HILwith melatonin treatment (HIL-M) group,HIL with Neu-P11 treatment (HIL-N) group.10 μL normal saline was instilled in NIL group and HIL group,while 10 μL 100 μmol · L-1 Mel/Neu-P11 treated in HIL-M group and HIL-N group.After 2 hours of rest,rats were placed in the Trendelenburg position duration 45 minutes.And then,IOP was measured every hour for 6 hours,and repeated it for a week.The excessive sodium pentobarbital was injected to SD rats at the end of the experiment.The rat eyeballs were took out to perform HE and immunohistochemical staining to detect retina GFAP protein expression.Results After a week,IOP in HIL group was (41.26 ± 1.73) mmHg (1 kPa =7.5 mmHg),NIL group was (13.61 ± 0.55) mmHg,which mean the Trendelenburg could induce high IOP in SD rats.Compared with the NIL group,the retinal becoming thick,the level of organization was not clear and the expression of GFAP protein was quite high in HIL group.At the same time,the GFAP protein expression and IOP were significantly weakened in HIL-M group and HIL-N group compared with HIL group.Conclusion Neu-P1 1 can reduce IOP,inhibit the activation of gliocyte,and decrease the expression of GFAP to protect the retina.

Aim To explore the effect of Neu-P11,a novel melatonin agonist with similar function of melatonin,on IOP of acute high IOP animals and the related mechanism.Methods The experiment used the Trendelenburg position(head low feet high position of 80°)to establish acute high IOP model.Rats were placed in the Trendelenburg position and used Tonopen XL contact tonometer to measure IOP(every 5 minutes measured once IOP,and the maximum value in 20 minutes)in 8 :00～9 :00 am.And then,thirty Sprague-Dawley rats(8 week-old)were divided into five groups: normal IOP+normal saline,high IOP+normal saline,high IOP+10 mg·kg-1 Mel,high IOP+20 mg·kg-1 Neu-P11,high IOP+50 mg·kg-1 Neu-P11.Put in a flat to rest 2 h,animals were placed in Trendelenburg position again and then,IOP was measured every hour in the flat by 6 hours.After excessive sodium pentobarbital administration continuous for 1 week,the serum was collected and stored for subsequent detection at the end of the experiment.The level of MDA,SOD and GSH-Px enzyme activity of the rat serum was tested by kit accordingly.HE staining method was used to identify the SD rat retinal morphological changes.Results Trendelenburg position could induce IOP of model group rats,which was increased by 202.9％(P<0.01)and the content of MDA,reduced the activity of SOD and GSH-Px enzyme,retinal thickening was observed and its level was not clear.Neu-P11/Mel could significantly improve oxidative stress level and retinal edema in rats.Conclusion Neu-P11 could reduce IOP of the acute high IOP animals,which might be involved in the lower level of oxidative stress in the body.

Head and neck tumors often have complex anatomical structures and are adjacent to important organs. Radiation injury caused by conventional radiotherapy technology is the main dose-limiting factor. Carbon ion beam has become the most ideal radiation to replace photon due to its excellent relative biological effect and Bragg peak. By 2019, 32 000 people worldwide have received carbon ion radiotherapy (CIRT). Despite the efficient tumor killing ability of this technology, radiation injury cannot be avoided. This article reviews the types and incidence of moderate to severe radiation injury caused by CIRT in head and neck cancer to provide a comprehensive understanding of the potential risks in CIRT.

Objective::To explore the effects of the biomimetic network membrane prepared by chitosan/gelatin/pectin on the proliferation and mineralization of mesenchymal stem cells (MSCs) , and to evaluate its feasibility of constructing tissue engineering bone.Methods:Chitosan, gelatin and pectin were made into a new biomimetic network membrane in a certain ratio by biomimetics.The experiment was divided into control group (MSCs+conventional medium) , material group (MSCs+network membrane+conventional medium) and material+OS group (MSCs+network membrane+OS medium) .The cell morphology was observed by inverted phase contrast microscope;the growth and secretion of extracellular matrix of the MSCs were observed under scanning electron microscope (SEM) .The proliferation of cells was determined by MTT assay (The MSCs were divided into negative control group and material group, and they were cultivated with blank medium and medium including materials) .The expression of calcium in MSCs was detected by Alizarin Red staining.Real-time polymerase chain reaction (RT-PCR) was used to determine the expression levels of osteocalcin (OC) mRNA and osteopontin (OPN) mRNA in the MSCs.Results:The network membrane was semitransparent thin film.The MSCs were short shuttle and clustered under inverted phase contrast microscope.After cultured for 7d, the MSCs were shuttle;after cultured for 14d, the number of MSCs was increased, with pseudo feet on the membrane;after cultured for21d, the MSCs clustered with a lot of neo-formed extracellular matrix.The MTT results showed that there was no significant difference in the proliferation level of MSCs between material group and negative control group (P＞0.05) .The Alizarin Red staining results showed that the MSCs in the network membrane were dyed orange red.The RT-PCR results showed that the expression levels of OC mRNA in the MSCs in material group and material+OS group were lower on the 7th and 14th days, but on the 21th day, the expression levels were significantly increased and reached the peak;the expression level of OC mRNA in the MSCs in material group was significantly increased on the 7th day, and the expression level reached the peak on the 14th day, then fell slightly on the 21th day;compared with control group, the expression levels of OC mRNA and OPN mRNA in the cells in material group and material+OS group at different time points were significantly increased (P＜0.01) , but there were no significant differences between material group and material+OS group (P＞0.05) .Conclusion:Chitosan/gelatin/pectin biomimetic network membrane has good biocompatibility, and MSCs can grow and proliferate well on the membrane.The membrane can induce the MSCs to express mineralization-related genes and proteins without inducers.

ObjectiveTo explore the biological mechanism of drought improving the quality of Rhizoma Atractylodis Chinensis and establish a new method for the production of high-quality medicinal materials. MethodThe fresh roots of Atractylodes chinensis were soaked in 0 （control）， 5%， 10%， and 20% PEG-6000 solutions. The changes in reactive oxygen species （ROS） level， antioxidant enzyme activity， activities of key enzymes in primary metabolism and secondary metabolism， and content of secondary metabolites were compared. ResultCompared with the control group， the treatment with 20% PEG for 2 days elevated the levels of superoxide anion radicals （O2-·）， hydrogen peroxide （H₂O₂）， and malondialdehyde （MDA） by 172.5%， 56.9%， and 14.7%， respectively. The treatment did not change the activity of superoxide dismutase （SOD）， reduced the peroxidase （POD） activity， and increased the catalase （CAT） activity by 10.8%. It increased the activities of 3-hydroxy-3-methylglutaryl-CoA reductase （HMGR）， phosphoenolpyruvate carboxylase （PEPC）， and acetyl-CoA carboxylase （ACC） by 49.9%， 12.1%， and 19.0%， respectively. Furthermore， the content of atractylodin， β-eudesmol， atractylone， and atractylenolide Ⅱ was increased by 51.0%， 36.9%， 47.1%， and 91.5%， respectively. The simulated drought stress can cause the burst of ROS in the fresh roots of A. chinensis， induce the physiological state of plants under drought， change the antioxidant system， and promote the massive synthesis of secondary metabolites in a short time. ConclusionPEG-6000-simulated drought stress can greatly improve the quality of A. chinensis in cultivation.