混合机胶质糖生产设备介绍之二

混合机械按物料特性及工艺要求的不同,有称混合机的,也有称捏和机、搅拌机等等。这方面,本刊93/2,3期已有专题论述。本文只就胶质糖混合机的特殊性方面作深一层的探讨。 胶质糖的原料主要为胶基、糖粉、葡萄糖等,其特点是粘性大、含水量低,用一般的混合设备是无法达到要求的。机械强度高、功率大、有夹套加热保温装置是必备条件。图1是国产胶质糖混合机结构示意图,由机座、电机及摆线减速器、夹套缸体、搅拌双浆、两端传动齿组、液压倾倒装置、电器控制箱等构成。

砂糖粉碎机——胶质糖生产设备介绍之一

粉碎机又称碾磨机,广泛应用于轻化工业,大多数食品加工厂几乎都少不了它,是胶质糖生产的重要设备之一。胶质糖产品的原料组成,55％以上为糖粉,糖粉质量的优劣,直接影响到成品的质量。 国内用于粉碎砂糖的设备。

The therapeutic mechanism of Shenyuan Gan in lipopolysaccharide-induced neuroinflammation in BV2 microglial cells

Objective To study the therapeutic effects of Shenyuan Gan(参远苷,SYG)on the inflammat-ory response in BV2 microglial cells induced by lipopolysaccharide(LPS).Methods The cytotoxicity of SYG to BV2 microglial cells was evaluated using a Cell Counting Kit-8(CCK-8)assay,and the effect of SYG concentrations on LPS-induced BV2 microglial cells was studied.The morphological changes were observed using an optical microscope.The nitric oxide(NO)concentration in cell culture supernatant was determined using Griess re-agent.The expression of cytokines and inflammatory mediators were also measured by an en-zyme-linked immunosorbent assay(ELISA).Western blot analysis was used to determine the levels of inducible NO synthase(iNOS),nuclear factor-kappa B(NF-κB)p65,alpha inhibitor of NF-κB(IκB-α),phosphorylation-IκB-α(p-IκB-α),NOD-like receptor 3(NLRP3),and cas-pase-1 expression.Moreover,the expression of iNOS,NLRP3,and ionized calcium binding adapter molecule 1(Iba1)was also observed using immunofluorescent staining.Results SYG had a low cytotoxic effect on BV2 microglial cells and could significantly decr-ease LPS-induced morphological changes of BV2 microglial cells(P<0.05).ELISA results showed that SYG significantly inhibited the LPS-induced increase in interleukin(IL)-1βand IL-6 in BV2 microglia cells(P<0.05),and Western blot analysis showed that the phosphoryla-tion levels of iNOS,NF-κB p65,and IκB-αas well as NLRP3 and caspase-1 expression were also significantly decreased,and IκB-αexpression was increased after SYG treatment(P<0.05,compared with the LPS-treated group).The immunofluorescence results were consist-ent with the Western blot results,and Iba1 staining indicated that the cell morphology tended to be resting.These results indicate that SYG has a certain inhibitory effect on LPS-induced inflammation in BV2 microglial cells.Conclusion SYG can inhibit LPS-induced release of inflammatory factors in BV2 microglial cells by affecting the phosphorylation levels of NF-κB p65 and IκB-α.SYG is a valuable candid-ate for treating neuroinflammation-related diseases.

Preparation and Properties of Collagen-Chitosan/Glycosaminoglycans as Candidate Tissue Engineering Biomaterials

A novel biomaterial scaffold was created from collagen chitosan/GAG. Its tensile strength was 8.6MPa(wet state)and degree of swelling water was 60%～75% with higer ultimate elongation 300%. Rabbit corneas of collagen chitosan/GAG implantation samples in vivo for biodegradation showed that the inplantion samples was complets biodegrable and digested afere 120 day. There was enought time to maintain cell growth,immigrating and proliferation. This biomaterials scaffold can be used for cell culture and in various tissue engineering fields.

The Hydrolyzation of Collagen by Fucoidan Olisosaccharide's Complex with Ce^(IV)

Fucoidan is such a polysaccharide that its hydroxies are easy to combine with lanthanons ion （Ce^IV） to form complex. This work obtained the complexes of three fucoidan oligosaccharides with different molecular weights F1 （〉5 000）, F2 （1 000-5 000） and F3 （〈 1 000） by hydrolyzing Oligosaccharide collagen with sulfuric acid. It is found that the fucoidan oligosaccharide F3 can form complex with more Ce^IV than F1 and F2. Hydrolyzing collagen with the complex was carried out to produce amino acid and peptides. All the three fucoidan oligosaccharide complexes with CeIV（ F1, F2, F3） can catalyze by the artificial hydrolytic enzyme, and the activity of the complex of F3 is the highest.

Cloning, expression and characterization of a novel esterase from a South China Sea sediment metagenome

Lipolytic enzymes, including esterases and lipases, represent a group of hydrolases that catalyze the cleavage and formation of ester bonds. A novel esterase gene, scsEst01, was cloned from a South China Sea sediment metagenome. The scsEst01 gene consisted of 921 bp encoding 307 amino acid residues. The predicted amino acid sequence shared less than 90% identity with other lipolytic enzymes in the NCBI nonredundant protein database. Scs Est01 was successfully co-expressed in E scherichia coli BL21(DE3) with chaperones(dnaK-dna J-grp E) to prevent the formation of inclusion bodies. The recombinant protein was purified on an immobilized metal ion affinity column containing chelating Sepharose charged with Ni2 +. The enzyme was characterized using p-nitrophenol butyrate as a substrate. Scs Est01 had the highest lipolytic activity at 35℃ and p H 8.0, indicative of a meso-thermophilic alkaline esterase. Scs Est01 was thermostable at 20℃. The lipolytic activity of scs Est01 was strongly increased by Fe2 +, Mn 2+ and 1% Tween 80 or Tween 20.

Investigation the Porous Collagen-Chitosan/Glycosaminoglycans for Corneal Cell Culture as Tissue Engineering Scaffold

The objective of this study was to produce the porous col lagen-chitosan/Gl ycosanminglycans(GAG) for corneal cell-seed implant as a t hree-dimensional tissue engineering scaffold to improve the regeneration cornea s.The effect of various content of glycerol as form porous agent to collagen-ch i tosan/GAG preserved a porous dimensional structure was investigated.The heat-dr ying was used to prepare porous collagen-chitosan /GAG scaffold.The pore morpho logy of collagen-chitosan/GAG was controlled by changing the concentration of g lycerol solution and drying methods.The porous structure morphology was observed by SEM.The diameter of the pores form 10 to 50 μm.The highly porous scaffold had interconnecting pores.The corneal cell morphology was observed under the li ght microscope.These results suggest that collagen-chitosan/GAG showed that cor neal cell have formed confluent layers and resemble the surface of normal cornea l cell surface.

Construction of recombinant plasmid pEGFP-C2-L539fs/47 and its expression in HEK293 cells

Objective:To reconstruct pEGFP-C2-L539fs/47,a HERG nonsense mutant in eukaryotic expression plasmid,and observe the fusion protein expressed in HEK293 cells(human embryo kidney cells).Methods:After double digestion of pcDNA3-L539fs/47 and pEGFP-C2-HERG with sbf I and Eco91 I,the small product fragment,from pcDNA3-L539fs/47,was subcloned into the big fragment of pEGFP-C2-HERG under T4 ligase.pEGFP-C2-L539fs/47 was identified by agarose gel electrophoresis and sequencing.pcDNA3-L539fs/47 and pEGFP-C2-L539fs/47 were transiently transfected into HEK293 cells by Lipofect,respectively.The expression of fusion protein in HEK293 cells was detected through immunofluorescence,laser confocal imaging scanning in vivo,Western blot and PCR.Results:Mutation region cDNA fragment(about 1 kb) and target vector fragment(about 7.2 kb) were ligated after purification and gel recovery.Agarose gel electrophoresis and sequencing successfully demonstrated eukaryotic expression plasmid pEGFP-C2-L539fs/47,constructed approximately 8.2 kb,sequencing consistent with template gene.The transfection efficiency of recombinant plasmid by fluorescence microscopy was more than60%.Western blot analysis detected pcDNA3-L539fs/47 expression of the protein size 60 KD,the expression of pEGFP-C2 fusion protein size of approximately 90 KD.The L539fs/47 gene expression in HEK293 cells was significant by PCR analysis.Confocal laser imaging showed that pEGFP-C2-L539fs/47 protein was successfully expressed in cytoplasm and cytomembrane of HEK293 cells.Conclusion:pEGFP-C2-L539fs/47 containing the HERG gene mutant was successfully constructed by double digestion method and expressed fusion protein in HEK293 cells,which laid a foundation for the further study on L539fs/47.

The use of a new functional glucose conjugate material, TPGS_(1000)-Glu, in treatment of brain glioma by incorporating into epirubicin liposomes

Most of antieancer agents can not be used for treatment of brain glioma due to the existence of the blood brain barrier （BBB）. The over-expression of glucose transporters （GLUTs） on the BBB and brain glioma cells enables the possibility that the GLUTs ligand modified drug carrier transports across the BBB, and targets to the brain glioma cells. The objectives of the present study were to synthesize a new glucose conjugate material, TPGS1000-Glu, develop a kind of TPGSI00o-Glu modified epirubicin liposomes, and evaluate their efficacy. The studies were performed on the BBB co-culture model and brain glioma cells in vitro. TPGS 1000-Glu was synthesized by conjugating TPGSlo00_COOH with 4-aminophenyl-[3-D-glucopyranoside （Glu）, and confirmed by MALDI-TOF-MS spectrum. TPGS^0oo-GIu modified epirubicin liposomes were prepared with a high drug encapsulation efficiency （〉97%）, a nanosize （approximately 90 nm）, and a minimal drug leakage in fetal bovine serum （FBS）-containing buffer system. The BBB co-culture model was established, and after applying TPGSl0oo-Glu modified epirubicin liposomes to the model, transport of liposomal drug across the BBB was evidenced. Besides, TPGS1000-Glu modified epirubicin liposomes showed the strongest cellular drug uptake and anti-glioma efficacy after transport across the BBB in vitro. The synthesized TPGS1000-Glu material could offer a new targeting ligand for the BBB, while the developed TPGS1000-Glu modified epirubicin liposomes might provide a potential anticancer formulation for treatment of brain glioma.

Bridging peripheral nerve defect with chitosan-collagen film

Objective: To seek new method for the treatment of peripheral nerve injury. Methods: In rat model with sciatic nerve defect, chitosan collagen film was sutured into conduit to bridge 5 mm , 10 mm nerve defects. Rats that underwent end to end anastomosis were taken as controls. General observation, electrophysiological study, histological study and image analysis were performed at 4, 8, 12 weeks postoperatively. Results: In 5 mm nerve defects, the quality of nerve regeneration was similar to that of the control group. For 10 mm nerve defect, nerve regeneration was inferior to that of the control group. Chitosan collagen film obviously degraded at 12 weeks postoperatively. Conclusions: Chitosan collagen film conduit can be used to bridge peripheral nerve defect.

Effects of chitosan on cell proliferation and collagen production of tendon sheath fibroblasts,epitenon tenocytes,and endotenon tenocytes

To study the proliferation and collagen production of tendon sheath fibroblasts, epitenon tenocytes, and endotenon tenocytes; and the effects of chitosan on cell proliferation and collagen production in the 3 cell types of rabbit flexor tendon. Methods ： Three cell lines of tendon sheath, epitenon, and endotenon were isolated from rabbit flexor tendon and cultured. Cell culture media was added with chitosan. The cell number and production of collagens Ⅰ, Ⅱ, and Ⅲ were measured and compared with those cultured without chitosan. The expression of type I collagen in tendon sheath fibroblasts was determined by quantitative analysis of reverse-transcription polymerase chain reaction. Results ： All 3 cell lines produced collagens Ⅰ, Ⅱ, and Ⅲ. Adding chitosan to cell media resulted in a significant decrease in cell number in all 3 cell lines. In addition, there was a significant decrease in collagens Ⅰ, Ⅱ, and Ⅲ production in all 3 cell lines as well as the expression levels of type I collagen in tendon sheath fibroblasts （ P 〈 0.05 ）. Conclusions： Chitosan can inhibit cell proliferation and collagen production of the tendon sheath, epitenon, and endotenon, and may provide a promising approach to obviating tendon adhesion formation clinically.

Inhibition of chemotherapy-related breast tumor EMT by application of redox-sensitive siRNA delivery system CSO-ss-SA/siRNA along with doxorubicin treatment

Metastasis is one of the main reasons causing death in cancer patients.It was reported that chemotherapy might induce metastasis.In order to uncover the mechanism of chemotherapy-induced metastasis and find solutions to inhibit treatment-induced metastasis,the relationship between epithelial-mesenchymal transition(EMT)and doxorubicin(DOX)treatment was investigated and a redox-sensitive small interfering RNA(siRNA)delivery system was designed.DOX-related reactive oxygen species(ROS)were found to be responsible for the invasiveness of tumor cells in vitro,causing enhanced EMT and cytoskeleton reconstruction regulated by Ras-related C3 botulinum toxin substrate 1(RAC1).In order to decrease RAC1,a redox-sensitive glycolipid drug delivery system(chitosan-ss-stearylamine conjugate(CSO-ss-SA))was designed to carry siRNA,forming a gene delivery system(CSO-ss-SA/siRNA)downregulating RAC1.CSO-ss-SA/siRNA exhibited an enhanced redox sensitivity compared to nonresponsive complexes in 10 mmol/L glutathione(GSH)and showed a significant safety.CSO-ss-SA/siRNA could effectively transmit siRNA into tumor cells,reducing the expression of RAC1 protein by 38.2%and decreasing the number of tumor-induced invasion cells by 42.5%.When combined with DOX,CSO-ss-SA/siRNA remarkably inhibited the chemotherapy-induced EMT in vivo and enhanced therapeutic efficiency.The present study indicates that RAC1 protein is a key regulator of chemotherapy-induced EMT and CSO-ss-SA/siRNA silencing RAC1 could efficiently decrease the tumor metastasis risk after chemotherapy.