9 research outputs found

    Phosphorus-nitrogen compounds. Part 48. Syntheses of the phosphazenium salts containing 2-pyridyl pendant arm: Structural characterizations, thermal analysis, antimicrobial and cytotoxic activity studies

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    The phosphazenium salts (protic ionic liquids, PILs/protic molten salts, PMOSs) (6a-6d and 7a) of the free phosphazene bases (4a-4d and 5a) were prepared by the reactions of the corresponding cyclotriphosphazenes with the bulky gentisic acid. The structures of the PMOS were evaluated using the elemental analyses, FTIR, 1H, 13C{1H} and 31P{1H} NMR data. The molecular and crystal structures of 4a and 6c were established by X-ray crystallography. The thermal properties of the PMOS were determined using TG and DTA techniques. On the other hand, the antimicrobial activities of the free phosphazene bases (4a-4d and 5a-5d) and PMOSs (6a-6d and 7a) were screened against the selected bacteria and yeast strains. The antimicrobial activities of the free phosphazene bases and the PMOSs were compared. The interactions of the phosphazenes and their salts with plasmid DNA were elucidated by the agarose gel electrophoresis. The evaluations of the cytotoxic activities of these compounds were also studied against to L929 fibroblast and breast cancer cells (MDA-MB-231).  

    Synthesis and structural and thermal properties of cyclotriphosphazene-based ionic liquids: tribological behavior and OFET application

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    Three new fully substituted starting materials (Pz1-3) were synthesized reacting dimethylaminoethanol, 3-dimethylamino-1-propanol, and 4-pyrridinemethanol, which were saltified using metallic sodium, with partly substituted phosphazene (Pz) compound. Phosphazene-based ionic liquids (PzILs), PzIL1-3, were obtained from the reaction of the starting materials with CH3I. New ionic liquids (PzIL1a-3a) were obtained by replacing the I- ions of these ionic liquids with the NTf2- anions. The structures of PzILs were elucidated by elemental analysis, FTIR, and H-1, C-13 {H-1}, and P-31 {H-1} NMR techniques. The thermal properties of all compounds were investigated using thermogravimetric (TG) analysis. Compared with the output materials, the thermal stability of the ionic liquids was found to be higher, 160, 199, and 228 degrees C for PzIL1-3 respectively, and 270, 204, and 287 degrees C for PzIL1a-3a respectively. At the same time, the viscosity measurements of PzIL1a-3a compounds obtained as liquids in room temperature were measured with a cone/plate viscometer. It is understood from the viscosity values that the fluidities of these compounds are as low as 864, 3801, and 423,700cP, respectively (water viscosity is 0.7977cP at 30 degrees C). In addition to these studies, sliding wear test was conducted at room temperature using AA7075 disc specimen against the stationary 100Cr6 steel ball. The wear protection of PzILs was determined considering the volume loss of AA7075

    Synthesis, and spectroscopic, thermal and dielectric properties of phosphazene based ionic liquids: OFET application and tribological behavior

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    Mono(4-fluorobenzyl)cyclotriphosphazene derivatives with (dimethylamino)ethoxy (Pz1a-2a) and (dimethylamino)propoxy (Pz1b-2b) chains were synthesized. The chain nitrogen atoms of fully substituted cyclotriphosphazene compounds were quaternized by treatment with CH3I to give phosphazene based ionic liquids (PzILs), PzIL1-PzIL4. Subsequent metathesis with LiN(SO2CF3)(2) gave the salts, PzIL1a-PzIL4a. The structures of the PzILs were confirmed by elemental analyses, FTIR and H-1, C-13{H-1}, and P-31{H-1} NMR techniques. The thermal properties of all compounds were described using thermogravimetric analysis (TGA). These newly synthesized PzILs were used as the dielectric layer in organic field effect transistors (OFETs). Both dielectric and OFET characterization were performed. Because of the high dielectric effect of the PzILs, the fabricated OFETs operated in the low voltage range. Furthermore, a sliding wear test was conducted at room temperature using an AA7075 disc specimen against a stationary 100Cr6 steel ball. The wear protection of the PzILs and 15W40 engine oil was determined by considering the volume loss of AA7075. The lowest coefficient of friction (COF) and wear loss were obtained with PzIL4a

    The epidemiology and economic impact of varicella-related hospitalizations in Turkey from 2008 to 2010: a nationwide survey during the pre-vaccine era (VARICOMP study)

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    Varicella can cause complications that are potentially serious and require hospitalization. Our current understanding of the causes and incidence of varicella-related hospitalization in Turkey is limited and sufficiently accurate epidemiological and economical information is lacking. The aim of this study was to estimate the annual incidence of varicella-related hospitalizations, describe the complications, and estimate the annual mortality and cost of varicella in children. VARICOMP is a multi-center study that was performed to provide epidemiological and economic data on hospitalization for varicella in children between 0 and 15 years of age from October 2008 to September 2010 in Turkey. According to medical records from 27 health care centers in 14 cities (representing 49.3% of the childhood population in Turkey), 824 children (73% previously healthy) were hospitalized for varicella over the 2-year period. Most cases occurred in the spring and early summer months. Most cases were in children under 5 years of age, and 29.5% were in children under 1 year of age. The estimated incidence of varicella-related hospitalization was 5.29-6.89 per 100,000 in all children between 0-15 years of age in Turkey, 21.7 to 28 per 100,000 children under 1 year of age, 9.8-13.8 per 100,000 children under 5 years of age, 3.96-6.52 per 100,000 children between 5 and 10 years of age and 0.42 to 0.71 per 100,000 children between 10 and 15 years of age. Among the 824 children, 212 (25.7%) were hospitalized because of primary varicella infection. The most common complications in children were secondary bacterial infection (23%), neurological (19.1%), and respiratory (17.5%) complications. Secondary bacterial infections (p < 0.001) and neurological complications (p < 0.001) were significantly more common in previously healthy children, whereas hematological complications (p < 0.001) were more commonly observed in children with underlying conditions. The median length of the hospital stay was 6 days, and it was longer in children with underlying conditions (< 0.001). The median cost of hospitalization per patient was 338andwassignificantlyhigherinchildrenwithunderlyingconditions(p<0.001).Theestimateddirectannualcost(notincludingthelossofparentalworktimeandschoolabsence)ofvaricellarelatedhospitalizationinchildrenundertheageof15yearsinTurkeywas338 and was significantly higher in children with underlying conditions (p < 0.001). The estimated direct annual cost (not including the loss of parental work time and school absence) of varicella-related hospitalization in children under the age of 15 years in Turkey was 856,190 to $1,407,006. According to our estimates, 882 to 1,450 children are hospitalized for varicella each year, reflecting a population-wide occurrence of 466-768 varicella cases per 100,000 children. In conclusion, this study confirms that varicella-related hospitalizations are not uncommon in children, and two thirds of these children are otherwise healthy. The annual cost of hospitalization for varicella reflects only a small part of the overall cost of this disease, as only a very few cases require hospital admission. The incidence of this disease was higher in children < 1 year of age, and there are no prevention strategies for these children other than population-wide vaccination. Universal vaccination is therefore the only realistic option for the prevention of severe complications and deaths. The surveillance of varicella-associated complications is essential for monitoring of the impact of varicella immunization
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