Background and Aims: The exfoliated human deciduous tooth contains multipotent stem cells [Stem Cell from Human Exfoliated Deciduous tooth (SHED)] that identified to be a population of highly proliferative and clonogenic. These cells are capable of differentiating into a variety of cell types including osteoblast/osteocyte, adiopcyte, chondrocyte and neural cell. The aim of this study was to evaluate the differentiation of SHED to osteoblast in standard osteogenic medium and comparing the results with medium which supplemented with glucosamine in form of Chitosan.Materials and Methods: Dental pulp cells were isolated from freshly extracted primary teeth, digested with 4 mg/ml collogenase/dispase, and grown in Dulbecco's modified Eagle's medium with 10 percent fetal bovine serum. The clonogenic potential of cells was performed after 3 weeks of culture. Flowcytometric analysis, performed at day 21 of culture to identify surface markers of mesenchymal stem cells. The cells from 3rd passage used for osteogenic differentiation in routine osteoinductive medium. Chitosan (10 mg/ml) was added to the culture medium of case group. Alizarin Red Staining and Alkaline Phosphatase (ALP) activity were done to evaluate osteogenic differentiation in the developing adherent layer on the third passage. The results were analyzed using T-test. For the analysis of normal distribution of data, non-parametric Kolmogrov-Smirnov test was used.Results: The colonogenic efficiency was more than 80%. Flowcytometric analysis showed that expression of mesenchymal stem cell marker CD90, CD105 and CD146 were positive in SHED, while hematopoietic cell marker CD34, CD45 and endothelial cell marker CD31 were negative. Quantitative analysis of Alizarin Red Staining demonstrated that: mineralized nodule formation was higher in the group supplemented with glucosamine (Chitosan). Results from Alkaline Phosphatase activity test, on day 21, demonstrated a significantly higher ALP activity in the group supplemented Chitosan (P<0.001).Conclusion: Stem cells isolated and cultured from exfoliated deciduous teeth pulp, can be differentiated to osteoblast. Addition of Chitosan can be beneficial to promote osteogenic differentiation of these cells.

The Holmium-166 radionuclide is one of the most effective radionuclides used to treat bone marrow cancer and rheumatoid arthritis. Among the recommended radionuclides used in radiation synovectomy, 166Ho has got much attention due to suitable decay properties such as short half-life, its high beta energy, gamma-ray emission with suitable energy for nuclear imaging, and the possibility of large-scale production in medium flux reactor. One method to deliver 166Ho to the target tissue is via the 166Dy/166Ho-Chitosan in vivo generator. Compared with other similar radiopharmaceuticals, using the in vivo generator to deliver 166Ho, causes minimal non-target tissue exposure and increased absorbed dose in the target tissue. In this work, the absorbed dose of 166Dy/166Ho-Chitosan radio-complex for radiosynovectomy purposes was calculated by GEANT4 and MCNPX. The obtained results were compared with each other. In addition, the dosimetry results of the mentioned radio-complex have been compared with the common radio complexes used for radio-synovectomy.

Research subject: In the last few years, the application of biotechnology for cleaning-up heavy metal-bearing solution is rapidly growing, but industrial usage of this category, however, needs to be more investigated. Research approach: In current research, Pseudomonas putida– Chitosan hybrid biosorbent capability for U(VI) biosorption in fixed– bed column was investigated. Main results: The results showed that increase in inlet concentration from 50 to 200 mg/L increased the biosorption capacity from 188. 75 to 429. 28 mg/g. In the column system, the sorption capacity was higher than that of the batch system because fixed-bed column make best use of the inlet concentration difference as sorption driving force. Decrease in inlet flow rate through increase in the residence time for better diffusion or interaction as well as greater access to binding sites for uranium ions caused an improvement in column performance. Decline in the biosorption capacity due to increase in the inlet flow rate demonstrated that intraparticle diffusion was the rate-controlling step. With decreasing in the sorbent particle size from 1. 5 to 1 mm, a significant increase in the biosorption capacity from 179. 02 to 296. 87 mg/g was achieved. FTIR and potentiometric titration confirmed that while – NH+3 was the dominant functional group in the Chitosan, – NH+3, – NH3, – OH, – COOH were responsible for the hybrid biosorbent. In conclusion, the present study indicated that Pseudomonas putida – Chitosan could be a suitable biosorbent for U(VI) biosorption from aqueous solution in the continuous system.

Introduction: Oral insulin is the most familiar and easiest way of prescribing insulin. Thus, the aim of this study was to produce newly formulated Chitosan-coated insulin nanoliposomes as well as evaluate their potential efficacy for delivery in the condition of in vitro.Materials and Methods: Nanoliposomes encapsulating insulin with negative surface charge were produced using the method of reverse phase evaporation Lecithin, cholesterol, cetyl-diphosphate and β-cyclodexterin were used for producing nanoliposomes. Then, nanoliposomes were coated with Chitosan solution using  incubation. Having been dissolved, the nanoliposomes were evaluated for encapsulation efficiency using the technique of spectrophotometry. Using incubation method, the destructive effect of Peptic and tryptic on the insulin containing nano capsules was determined and compared to their effect on free insulin.Results: Insulin entrapment efficacy for the newly-formulated nanoliposomes was significantly (p<0.05) higher (79±0.16) than that of the other formulations. In all conditions, the insulin contained in Chitosan–coated nanoliposomes was highly protected from digestive effect of peptic and tryptic as compared to the uncoated nanoliposomes which did not protect the insulin from digestion.Conclusion: The results clearly suggest that the produced nanoliposomes may be considered as an appropriate alternative for the purpose of oral insulin delivery.

In this work, Pt, Fe and Co nanoparticles were prepared by chemical reduction of the metal salts in Chitosan as the support. NaBH4 was used as the reducing agent Pt-Fe, Pt-Co and Pt-Fe-Co-Chitosan nanocomposites were synthesized and characterized by UV–Vis spectra and Transmission electron microscopy images. GC/Pt-Chitosan, GC/Pt-Co-Chitosan, GC/ Pt-Fe-Chitosan and GC/Pt-Co-Fe-Chitosan electrodes were prepared.The performances of these electrodes for methanol electrooxidation were investigated through cyclic voltammetric and chronoamperometric curves. The effect of some experimental factors such as the amounts of Fe and Co nanoparticles dispersed in Chitosan, methanol concentration and scan rate were studied and the optimum conditions were determined.The effect of temperature was also investigated and the activation energies were calculated. The performance of Pt-Fe-Co-Chitosan nanocomposites was determined in a direct methanol fuel cell in different conditions.The electrochemical and fuel cell measurements showed that Pt-Fe-CoChitosan nanocatalyst has the best activity for electrooxidation of methanol among all different compositions electrodes.

Background and purpose: This study compared the effects of intraperitoneal injections of ZnO/Chitosan nanocomposite and ZnO nanoparticles on histopathology of kidney in thioacetamideintoxicated rats. Materials and methods: Twenty-eight male rats were randomly allocated into a healthy control group (negative control), positive control group (thioacetamide-intoxicated rats), thioacetamideintoxicated + ZnO nanoparticles, and thioacetamide-iontoxicated + ZnO/Chitosan nanocomposite. Nephropathy was induced by intraperitoneal injection of thioacetamide (50 mg/kg IP) three times (24h interval). The treatment groups were treated with ZnO nanocomposites (5mg/kg) and ZnO nanoparticles (5mg/kg) intraperitoneally for four weeks. Then, serum BUN and creatinine levels were measured. Afterwards, the rats were euthanized and kidney samples were separated for histological examinations. Results: There were significant increases in serum BUN and creatinine levels in thioacetamideintoxicated rats compared to those in the control group (P<0. 05). Compared to the control group, ZnO nanoparticles – treated group was found with significantly higher serum BUN and creatinine levels (P<0. 05). There was no significant difference between the rats treated with ZnO/Chitosan nanocomposites and the positive control group in BUN and creatinine levels (P>0. 05). In histological analysis, tubular necrosis and glomerular fibrosis were observed in treatment groups. Conclusion: This study showed that ZnO nanoparticles can increase nephrotoxicity induced by thioacetamide, but, ZnO/Chitosan nanocomposite had no effect on thioacetamide induced nephrotoxicity.

Currently, one of the most common ways to use the drug is to take it orally. It is easier and less painful than other common methods, such as intravenous or intramuscular injections. However, the effectiveness of drugs in these conditions is very limited due to poor pharmacokinetic behaviors and the sensitive structures of the drug molecules. Therefore, drugs need to be protected along the way to reach the drug delivery destination. It is important to design nanocarriers that are resistant to the acidic fluid of the stomach while changes in the intestinal fluid due to the environment of the gastrointestinal tract, such as the significant difference in the pH of the gastric and intestines. Chitosan (CS), a cationic polysaccharide, has received widespread attention due to its inherent mucosal adhesion properties, modulation of epithelial tight junction integrity, biocompatibility, biodegradability, improved stability, low toxicity, simple and gentle preparation methods, and various drug delivery solutions. Chitosan nanoparticles are prepared and characterized by different techniques. In addition, Chitosan derivatives such as thiolated and carboxylated Chitosan have been investigated to increase the effectiveness of oral drug absorption, effective dose control, and reduced side effects. Moreover, the synthesis of Chitosan nanoparticles, different synthesis methods, their widespread applications as oral drug delivery carriers, and their effects on drug delivery were investigated. This study aims to further development of these nanoparticles as effective therapeutic and diagnostic carriers in the future.

Background and aim: Chitosan has the property of inhibition of the growth of many pathogenic bacteria and fungi. Tissue conditioners are good substances for the growth and colonization of a variety of micro-organisms. The aim of this research was to investigate the antibacterial and antifungal properties of Chitosan, ZnO and Ag nanoparticles added to tissue conditioners. Material and Method: In this clinical trial study, 42 patients were randomly divided into 7 groups. In first group, the patients received the tissue conditioners (control group) and the second to seventh groups received the tissue conditioners included Chitosan, ZnO and Ag by weight percentage of 0. 675, 1. 25, 2. 5, 5, 10, 20. After 24 and 48 hours using these substances, the microbial culture inside the mouth and denture was done by sterile swap. Results: Complete inhibition of growth at 24 h and 48 h occurred in Candida albicans at 2. 5 % concentration and in Enterococcus faecalis, Pseudomonas aeruginosa and Streptococcus mutans at 5% concentration of Chitosan, ZnO and Ag nanoparticles. Over time, the growth rate of Candida albicans, Enterococcus faecalis, Pseudomonas aeruginosa and Streptococcus mutans was decreased. Conclusion: Increasing the concentration of nanoparticles increases the growth inhibition in all studied microorganisms. By increase of growth inhibition, the growth of microorganisms also increases. An enhancement of 5% in the concentration of tissue conditioners results in complete inhibition of the studied microorganisms.