Browsing by Author "Keskin H."

Now showing 1 - 2 of 2

Bonding strengths of poly(vinyl acetate), Desmodur-VTKA, phenol-formaldehyde and urea-formaldehyde adhesives in wood materials impregnated with Vacsol Azure
(2009-10-01) Keskin H.; Atar M.; Akyildiz M.
This study has been performed to determine the impacts of Vacsol Azure (VA) on the bonding strength of poly(vinyl acetate) (PVAc), Desmodur-VTKA (D-VTKA), urea-formaldehyde (UF) and phenol-formaldehyde (PF) adhesives on some impregnated wood materials. To this end, the test samples prepared from Oriental beech (Fagus orientalis Lipsky), European oak (Quercus petraea Liebl.), Scotch pine (Pinus sylvestris Lipsky), European linden (Tilia cordata) and Lombardy poplar (Populus nigra Lipsky) woods materials were treated with Vacsol Azure by the Vac-Vac double vacuum impregnation process of ASTM D 1413 standards and directions of the manufacturer. After impregnation, bonding strength test (based on BS EN 205) was applied on both sanded connection surfaces jointed by PVAc, D-VTKA, UF and PF adhesives. Consequently, in the interaction of the impregnated wood materials and adhesive types, the highest bonding strength was obtained in Oriental beech + PVAc (9.707 N mm-2) and the lowest was obtained in Lombardy poplar + UF (3.758 N mm-2). In consequence, in the massive constructions and furniture elements that the bonding strength after the impregnation with Vacsol Azure is of great concern, bonding with PVAc of Oriental beech wood materials could be recommended. © 2009 Elsevier Ltd. All rights reserved.
Effect of Tocilizumab on Acinetobacter baumannii Lung Infection in an Immunosuppressed Rat Model
(2022-01-01) Celebi D.; Halici Z.; Celebi O.; Akgun N.; Keskin H.; Cinar I.; Halici I.; Cinisli K.T.; Yildirim S.
Our study aimed to investigate effect of tocilizumab on the lung tissue in the presence of Acinetobacter baumannii infection in immunosuppressed rats. A forty-eight female Wistar albino rats were divided equally into eight groups: Group 1: Healthy (H), Group 2: Immunosuppressed (IM), Group 3: Healthy rats given A. baumannii bacteria (H+BAC), Group 4: Immunosuppressed rats given A. baumannii bacteria (IM+BAC), Group 5: Healthy rats given tocilizumab (H+TCZ), Group 6: Immunosuppressed rats given tocilizumab (IM+TCZ), Group 7: Healthy rats given A. baumannii bacteria and tocilizumab (H+BAC+TCZ), Group 8: Immunosuppressed rats given tocilizumab and A. baumannii bacteria (IM+BAC+TCZ). Fourteen days after the immunosuppression of group 2, 4, 6 and 8 with hydrocortisone, group 3, 4, 7 and 8 were A. baumannii was dropped into the trachea. One hour after A. baumannii application, TCZ was administered to Groups 5, 6, 7 and 8. NF-κB, IL-6 and NLRP3 mRNA expressions were decreased in the IM group compared to the healthy group (P<0.05). Although NF-κB, IL-6 and NLRP3 mRNA expression decreased in the IM+TCZ group compared to the healthy group (P<0.05) NF-κB, IL-6 and NLRP3 mRNA expression increased in the H+TCZ group (P<0.05). Despite decreasing cytokines, A. baumannii has been shown to increase infection-related lung injury. This suggests that in patients currently or recently using steroids, tocilizumab may increase organ damage due to opportunistic infection.