Poly[(μ3-quinoline-6-carboxyl­ato-κ3 N:O:O′)silver(I)]

In the title coordination polymer, [Ag(C10H6NO2)]n, the AgI cation is coordinated by two O atoms and one N atom from three 6-quinoline­carboxyl­ate anions in a distorted T-shaped AgNO2 geometry, in which the O—Ag—O angle is 160.44 (9)°. The 6-quinoline­carboxyl­ate anion bridges three Ag+ cations, forming a nearly planar polymeric sheet parallel to (101). The distance between Ag+ cations bridged by the carboxyl group is 2.9200 (5) Å. In the crystal, π–π stacking is observed between parallel quinoline ring systems, the centroid–centroid distance being 3.7735 (16) Å

Poly[[μ-(3-aminopyridine)-κ2N:N′-μ-chlorido-chlorido(N,N′-dimethylformamide-κO)nickel(II)] N,N′-dimethylformamide monosolvate]

The title compound, {[NiCl2(C5H6N2)(C3H7NO)]·C3H7NO}n, is a two-dimensional polymer in which the NiII atom is coordinated by two N atoms from two 3-aminopyridine ligands, one O atom from a dimethylformamide (DMF) group, one terminal Cl and two bridging Cl atoms in a distorted octahedral geometry. The NiII atoms are bridged by the 3-aminopyridine ligands [Ni...N = 6.7048 (3) Å] and Cl− atoms [Ni...N = 3.5698 (3) Å], forming (4,4) two-dimensional nets. The DMF solvent molecule and the non-bridged Cl− ions participate in N—H...O and N—H...Cl hydrogen bonds with the amino groups

In Vivo Osseointegration Performance of Titanium Dioxide Coating Modified Polyetheretherketone Using Arc Ion Plating for Spinal Implant Application

Polyetheretherketone (PEEK), which has biomechanical performance similar to that of human cancellous bone, is used widely as a spinal implant material. However, its bioinertness and hydrophobic surface properties result in poor osseointegration. This study applies a novel modification method, arc ion plating (AIP), that produces a highly osteoblast compatible titanium dioxide (TiO2) coatings on a PEEK substrate. This PEEK with TiO2 coating (TiO2/PEEK) was implanted into the femurs of New Zealand white male rabbits to evaluate its in vivo performance by the push-out test and histological observation. Analytical results show that AIP can prepare TiO2 coatings on bullet-shaped PEEK substrates as implant materials. After prolonged implantation in rabbits, no signs of inflammation existed. Newly regenerated bone formed more prominently with the TiO2/PEEK implant by histological observation. The shear strength of the bone/implant interface increases as implantation period increases. Most importantly, bone bonding performance of the TiO2/PEEK implant was superior to that of bare PEEK. The rutile-TiO2 coatings achieved better osseointegration than the anatase-TiO2 coatings. Therefore, AIP-TiO2 can serve as a novel surface modification method on PEEK for spinal interbody fusion cages

Organocatalyzed ring-opening copolymerization of α-bromo-γ-butyrolactone with ε-caprolactone for the synthesis of functional aliphatic polyesters – pre-polymers for graft copolymerization

Diphenyl phosphate (DPP) was exploited as an organocatalyst to synthesize copolymers by ring-opening polymerization with α-bromo-γ-butyrolactone (αBrγBL) and ε-caprolactone (εCL) as monomers and polyethylene glycol (PEG) as initiator. The conversion rates of monomers and molecular weights of copolymers synthesized under different conditions were determined by 1H-NMR. The 1H-NMR results showed that the copolymers of αBrγBL and εCL initiated by PEG (PEGCB) were successfully synthesized and the conversions of εCL were relatively high (＞70%), while the conversions of αBrγBL were relatively low (＜26%). The highest molar ratio of αBrγBL to εCL units in these copolymers is 0.17, when the copolymerization was carried out at 100℃ for 17h. The bromine atoms hanged on the chain of the copolymers PEGCB provide a good opportunity to construct graft copolymers via atom transfer radical polymerization (ATRP). The subsequent grafting of 2-(dimethylamino)ethyl methacrylate (DMAEMA) was conducted by using PEGCB3 as macroinitiator, CuBr/N,N’,N’,N”,N”- pentamethyldiethylenetriamine (PMDETA) as catalysts and toluene/anisole as solvents via ATRP. According to the analysis of 1H-NMR, the grafting efficiency, grafting ratio and grafting frequency were 22.4%, 160.7% and 1133.8, respectively

Relationship Between Perinatal and Neonatal Indices and Intelligence Quotient in Very Low Birth Weight Infants at the Age of 6 or 8 Years

The majority of children born with very low birth weight (VLBW; < 1500 g) enter mainstream schools. They experience significant neurodevelopmental disabilities during childhood. The specific aims of our study were to evaluate the neonatal outcomes of VLBW infants and whether they would influence intelligence quotient (IQ), cognitive function and learning disabilities at the age of 6 or 8 years. Methods: We enrolled VLBW neonates who weighed less than 1500 g and who were delivered at Shin-Kong Wu Ho-Su Memorial Hospital in 1996 and 1999. The psychological assessments were applied with the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) for age 6 and Wechsler Intelligence Scale for Children-Third Edition (WISC-III) for age 8. We recorded their demographic data, ventilation duration by days, length of stay, use of surfactant, respiratory distress syndrome (RDS), and other complications. Results: According to whether the full scale intelligence quotient (FSIQ) was above or below the average score (FSIQ = 90), we divided VLBW children into two groups (< 90, n = 17; ≥ 90, n = 21). The children with lower gestational age had lower FSIQ (p = 0.013). The higher FSIQ group (≥ 90) showed more prenatal steroid use (5/17, 29.4% vs. 14/21, 66.7%; p = 0.049). There were more boys in the lower FSIQ group (< 90, 13/17, 76.5% vs. ≥90, 7/21, 33.3%; p = 0.011). The average IQ scores were 78.11 ± 9.05 and 102.57 ± 8.89 in the FSIQ < 90 and FSIQ < 90 groups, respectively. The groups were similar in ventilation duration by days, use of surfactant, frequency of sepsis, RDS, bronchopulmonary dysplasia, patent ductus arteriosus, intraventricular hemorrhage and retinopathy of prematurity. Conclusion: Conclusion: In our study, the children with lower gestational age had lower FSIQ. There was no significant association between small for gestational age and IQ performance. The neonatal outcomes of VLBW infants did have less impact on IQ performance later in life

Polyurethane/Nanosilver-Doped Halloysite Nanocomposites: Thermal, Mechanical Properties, and Antibacterial Properties

In this study, the researchers successfully embellished the surface of halloysite (Ag/HNTs) with silver using halloysite, silver nitrate (AgNO3), and polyvinylpyrrolidone (PVP). The researchers then prepared polyurethane that contained pyridine ring by using 4,4&prime;-diphenylmethane diisocyanate (MDI) and polytetramethylene glycol (PTMG) as the hard chain segment and the soft chain segment of polyurethane (PU), as well as 2,6-pyridinedimethanol (2,6-PDM) as the chain extension agent. This was followed by the preparation of Ag/HNTs/PUs nanocomposite thin films, achieved by mixing Ag/HNTs with different ratios into polyurethane that contains pyridine ring. First, the Ag/HNTs powders were analyzed using energy-dispersive X-ray spectroscopy, X-ray diffraction, and transmission electron microscopy. Subsequently, Fourier-transform infrared spectroscopy was used to examine the dispersibility of Ag/HNTs in PU, whereas the thermal stability and the viscoelasticity of Ag/HNTs/PU were examined using thermal gravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. When the mechanical properties of Ag/HNTs/PU were tested using a universal strength tester, the results indicated a maximum increase of 109.5% in tensile strength. The researchers then examined the surface roughness and the hydrophobic ability of the Ag/HNTs/PU thin films by using atomic force microscopy and water contact angle. Lastly, antibacterial testing on Escherichia coli revealed that when the additive of Ag/HNTs reached 2.0 wt%, 99.3% of the E. coli were eliminated. These results indicated that the addition of Ag/HNTs into PU could enhance the thermal stability, mechanical properties, and antibacterial properties of PU, implying the potential of Ag/HNTs-02 as biomedicine material