1.Evaluation of self-prepared absorbable hemostatic cellulose fibrils.
Lingshuang WANG ; Jianxing TONG ; Zhezhe ZHAO ; Xiaochun YANG
Journal of Zhejiang University. Medical sciences 2021;50(5):633-641
To evaluate the effectiveness and safety of self-prepared absorbable hemostatic fibrils.A kind of absorbable hemostatic fibrils were prepared by self-developed patent technique. The physical form and molecular structure of the fibrils and a marketed product Surgicel were characterized by general observation and infrared spectroscopy; the carboxyl content, pH value and relative molecular mass of fibrils were determined by potentiometric titration method, pH meter and copper ethylenediamine method, respectively. The behavior of the fibrils and Surgicel in contact with blood was observed by inverted microscope, the cytotoxicity was evaluated by agarose diffusion cell assay . The external iliac artery hemorrhage model and the back muscle infiltration model in rats were established. The hemostatic effectiveness of the fibrils was investigated by hemostasis time and blood weight, and the degradation and biosafety of fibrils were investigated by observation photography, immune organ weighing, hematology and coagulation index measuring, and histopathological examination. The fibrils and Surgicel had similar molecular structures. Compared with the raw material regenerated cellulose, the typical carboxyl stretching vibration absorption peak of -COOH appeared near in both fibrils and Surgicel. The carboxyl content of the two materials was about 20%, and the pH value was about 3. The relative molecular mass of the fibers after oxidation was 4466±79, which was close to that of Surgicel(>0.05). After contacting with blood, the volume of fibrils and Surgicel expanded, and absorbed blood of dozens of times as their own weight. The results of agar diffusion test showed that the fibrils had no cytotoxicity. The results of animal experiments showed that the hemostasis completed within and there was no significant difference in blood weight and speed of hemostasis between two products (both >0.05). The fibrils could be degraded 1 week after being implanted to the bleeding sites of the muscle. There were no pathological effects on the appearance, body weight, food intake, immunological tissue thymus, spleen, lymph nodes, hematology and coagulation indexes of the rats, and no obvious abnormality found in the histopathological examination. The prepared absorbable hemostatic fibrils have excellent biological safety and effectiveness.
Animals
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Cellulose/pharmacology*
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Hemostasis
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Hemostatics/pharmacology*
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Rats
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Spleen
2.Preparation of complex chitosan microcapsule and its application in controlled release of vitamin D2.
Journal of Biomedical Engineering 2003;20(1):26-29
In this work a system which consists of chitosan (CS) microcores entrapped within enteric polymer is presented. Vitamin D2, used as a model drug, was efficiently entrapped within CS microcores using spray-drying and then microencapsulated into ethylic cellulose(EC). The morphology and release properties of microcapsules were tested. The influential factors of preparation conditions included molecular weight of chitosan, concentration of chitosan solution, concentration of acetic acid, loading of vitamin D2 were discussed. The results of in vitro release studies showed that the microcapsules prepared in this article could realize sustained release in intestine.
Capsules
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Cellulose
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analogs & derivatives
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pharmacology
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Chitin
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analogs & derivatives
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pharmacology
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Chitosan
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Delayed-Action Preparations
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Drug Compounding
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Drug Delivery Systems
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Ergocalciferols
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pharmacology
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In Vitro Techniques
3.The study and clinical application of absorbable hemostatic agent.
Journal of Biomedical Engineering 2009;26(4):922-926
This paper reviews the mechanisms and properties of different absorbable hemostatic agents. The development tendency of absorbable hemostatic agent is forecasted. Its' qualities of being useful to surgeons are introduced and are embodied in surgeon's comprehending of the hemostatic characteristic of absorbable hemostatic agents as well as in their clinical use of such agents accurately. At the same time, the researchers in pursuit of the medical materials can work with reference to the data herein presented.
Absorption
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Animals
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Blood Loss, Surgical
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prevention & control
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Cellulose, Oxidized
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administration & dosage
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pharmacology
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Chitosan
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administration & dosage
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pharmacology
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Fibrin Tissue Adhesive
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administration & dosage
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pharmacology
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Gelatin Sponge, Absorbable
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administration & dosage
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pharmacology
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Hemostatics
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administration & dosage
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pharmacology
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Humans
4.A kinetic approach to evaluate salinity effects on carbon mineralization in a plant residue-amended soil.
Farshid NOURBAKHSH ; Ahmad R SHEIKH-HOSSEINI
Journal of Zhejiang University. Science. B 2006;7(10):788-793
The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralization kinetics in a soil amended with alfalfa, wheat and corn residues. A factorial combination of two salinity levels (0.97 and 18.2 dS/m) and four levels of plant residues (control, alfalfa, wheat and corn) with three replications was performed. A first order kinetic model was used to describe the C mineralization and to calculate the potentially mineralizable C. The CO(2)-C evolved under non-saline condition, ranged from 814.6 to 4842.4 mg CO(2)-C/kg in control and alfalfa residue-amended soils, respectively. Salinization reduced the rates of CO(2) evolution by 18.7%, 6.2% and 5.2% in alfalfa, wheat and corn residue-amended soils, respectively. Potentially mineralizable C (C(0)) was reduced significantly in salinized alfalfa residue-treated soils whereas, no significant difference was observed for control treatments as well as wheat and corn residue-treated soils. We concluded that the response pattern of C mineralization to salinity stress depended on the plant residue quality and duration of incubation.
Carbon
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chemistry
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Carbon Dioxide
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chemistry
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Cellulose
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metabolism
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Ecosystem
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Kinetics
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Medicago sativa
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metabolism
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Models, Chemical
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Plants
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metabolism
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Salts
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chemistry
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pharmacology
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Soil
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Soil Pollutants
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Triticum
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metabolism
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Zea mays
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metabolism
5.Preparation and antibacterial capacity of artificial skin loaded with nanoparticles silver using bacterial cellulose.
Dongping SUN ; Jiazhi YANG ; Jun LI ; Lingli ZHOU ; Junwei YU
Journal of Biomedical Engineering 2009;26(5):1034-1038
In the present paper, in-situ preparation of silver nanoparticles have been conducted in 3D network structure of BC membrane through liquid phase chemical deoxidization method. The characterization of products was investigated using scanning electron microscopy (SEM), infrared spectroscopy (IR), energy dispersion spectrometry (SEM-EDS). The absorbing water capacity and preserving water capacity of substitutes and the antibacterial capacities of antibacterial agent-loaded artificial skin were tested. The results showed the silver nanoparticles were approximately spherical particles with an average diameter of 45nm, and were noted to have excellent sterilizing efficacy the efficiency of against Escherichia coli, yeast and Candida albicans.
Anti-Bacterial Agents
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pharmacology
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Bacteria
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chemistry
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Candida albicans
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drug effects
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Cellulose
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chemistry
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Escherichia coli
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drug effects
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Humans
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Metal Nanoparticles
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chemistry
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Microbial Sensitivity Tests
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Silver
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Skin, Artificial
6.Effects of bagasse polysaccharide on the immune functions of immunosuppressed mice.
Qiang LIU ; Yu-hong SONG ; Hui LI ; Yu CAI ; Xue-gang SUN ; Zhi-liang CHEN
Journal of Southern Medical University 2008;28(10):1911-1913
OBJECTIVETo observe the effects of bagasse polysaccharide on the immune functions of immunosuppressed mice.
METHODSImmunosuppressed mouse models were established by intraperitoneal injections with cyclophosphamide followed by daily intragastric administration of bagasse polysaccharide. After the treatments, the mice were examined for immune organ weight index, phagocytotic function of the macrophages, delayed type hypersensitivity, serum IgM level following exposure to chicken red blood cells, formation of hemolytic plaques, T cell percentage and lymphocyte transformation.
RESULTSTreatment of the immunosuppressed mice with bagasse polysaccharide at the daily dose of 200 and 400 mg/kg significantly increased the weight of the immune organs, phagocytotic function of the macrophages, delayed type hypersensitivity, serum IgM level against chicken red blood cells, formation of hemolytic plaques, T cell percentage and lymphocyte transformation.
CONCLUSIONBagasse polysaccharide can enhance the immune functions of immunosuppressed mice.
Animals ; Cellulose ; chemistry ; Cyclophosphamide ; Female ; Immunocompromised Host ; immunology ; Lymphocyte Activation ; drug effects ; Macrophages ; immunology ; Male ; Mice ; Phagocytosis ; drug effects ; Polysaccharides ; pharmacology ; Random Allocation