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In the present study, some new 1,2,3-triazole-tethered analogues of N-northebaine were designed and synthesized. The anti-bacterial properties of novel thebaine derivatives were studied on Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Based on the results, compounds 5b, 5j and 5m showed the best activities against S. aureus (minimum inhibitory concentration (MIC) ~ 25 µM) compared to the parent compound (MIC = 321 µM). The most active anti-bacterial derivatives (i.e., 5b, 5j and 5m) and thebaine were considered as potent anti-bacterial wound healing agents. In this regard, fibroblast cell cytotoxicity and proliferation as well as anti-hemolytic activities of the mentioned compounds were studied. The cytotoxicity assay by using 3-[4,5-dimethylthiazol-2-yl] 2,5-diphenyltetrazolium bromide (MTT) on Human dermal fibroblast cell lines (HDF) revealed that products 5j and 5m didn’t show inhibition of cell line growth after 24 hours and no further cytotoxic activity for a longer period (72 hours). Based on the investigation results on blood cell disruption for releasing of hemoglobin, compound 5j didn’t exhibit any hemolysis activity in different doses.

Reaction between 4-hydroxy-6-methyl-2H-pyran-2-one and aldehydes with 2-methylpyridine in dioxane under catalyst-free conditions provided a simple and efficient one-pot route for the synthesis of 3...

Copper (Cu) ions have been found to exert antibacterial and angiogenic effects. However, some studies have indicated that it inhibits osteogenesis at high concentrations. On the other hand, L-arginine (Arg) is a semi-essential amino acid required for various biological processes, including osteogenic and angiogenic activities. As a result, we hypothesized that combining Arg with Cu ions would reduce its inhibitory effects on osteogenesis while increasing its angiogenic and antibacterial capabilities. To assess osteogenic and angiogenic activities, we employed rat bone marrow mesenchymal stem cells (MSCs) and human umbilical vein endothelial cells (HUVECs), respectively. The gram-positive bacteria Staphylococcus epidermidis (S. epidermidis), Staphylococcus aureus (S. aureus), and the gram-negative bacterium Escherichia coli (E. coli) were used to investigate bacterial behaviors. According to ALP activity and calcium deposition outcomes, copper ions inhibited osteogenic development of MSCs at 100 µM; however, Arg supplementation somewhat mitigated the inhibitory effects. Furthermore, Copper and Arg synergistically stimulated migration and tube formation of HUVECs. According to our findings, copper ions and Arg in the range of 1-100 µM had no antibacterial effect on any examined bacteria. However, at a dose of 20 mM, copper demonstrated antibacterial activity, which was boosted by Arg. Overall, these findings suggest that a combination of copper and Arg may be more beneficial for bone regeneration than either copper or Arg alone.

The ultimate prospect of tissue engineering is to create autologous tissue grafts for future replacement therapies through utilization of cells and biomaterials simultaneously. Bio-printing is a novel technique, a growing field that is leading to the global revolution in medical sciences that has gained significant attention. Bio-printing has the potential to be used in producing human engineered tissues like bone and skin which then ultimately can be used in the clinics. In this paper, the 3D bio-printing applications of the engineered human tissues that are available (skin and bone) are reviewed. It is evident that various tissue engineering techniques have been applied in the fabrication of skin tissue; therefore, it leads to introduce tissue substitutes such as complementary, split-thickness skin graft, allografts, acellular dermal substitutes and cellularized graft-like commercial products, i.e., Dermagraft and Apligraf. Also, some bone scaffolds based on hydroxyapatite and biphasic calcium phosphate are available in the market. The technology of bio-printing has got validated for bone and skin tissue fabrication, and it is hoped that other tissues could be produced by this technique.

This study investigated the relationship between trade credit and monetary policy and conservatism. The population consisted of 74 corporates listed on Tehran Stock Exchange from 2009 to 2015. Methodology: Dependent variable was traded credit. Given data was gathered and categorized in Excel file as a data reference. Also, the hypothesis was tested using multivariate regression models based on integrated data techniques through econometrics Eviews software. Results: Results suggested that high conservatism corporates had more trade credit and there was a positive significant relationship between conservatism level and trade credit. Conclusion: Also, there was a positive significant relationship between tight monetary policy and trade credit.

Some metal hydrogen sulfates were used as acid catalysts in the N-acylation of different sulfonamides using carboxylic acid chlorides and anhydrides as acylating agents under both heterogeneous and solvent-free conditions. Al(HSO 4 ) 3 and Zr(HSO 4 ) 4 were found to have the highest activity and catalyze the reactions efficiently to furnish the primary N -acyl sulfonamides (RCONHSO 2 R′), secondary N -acylsulfonamides (RCONR″SO 2 R′) and bis- N -acylsulfonamnides [RCO(SO 2 R′)N-R″-N(SO 2 R′)COR] in good to high yield. The mild reaction conditions, inexpensive and low toxicity of catalysts and easy work-up procedure make this method attractive.

Some metal hydrogen sulfates were used as acid catalysts in the N-acylation of different sulfonamides using carboxylic acid chlorides and anhydrides as acylating agents under both heterogeneous and solvent-free conditions. Al(HSO 4 ) 3 and Zr(HSO 4 ) 4 were found to have the highest activity and catalyze the reactions efficiently to furnish the primary N -acyl sulfonamides (RCONHSO 2 R′), secondary N -acylsulfonamides (RCONR″SO 2 R′) and bis- N -acylsulfonamnides [RCO(SO 2 R′)N-R″-N(SO 2 R′)COR] in good to high yield. The mild reaction conditions, inexpensive and low toxicity of catalysts and easy work-up procedure make this method attractive.