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1. 血栓溶解療法後の冠動脈再梗塞の予測因子 predictors of coronary artery reocclusion following fibrinolysis thrombolysis

English Journal

Microrheology and Microstructure of Fmoc-Derivative Hydrogels.

Aufderhorst-Roberts A1, Frith WJ, Kirkland M, Donald AM.Author information 1Cavendish Laboratory, Department of Physics, University of Cambridge , JJ Thomson Avenue, Cambridge, CB3 0HE U.K.AbstractThe viscoelasticity of hydrogel networks formed from the low-molecular-weight hydrogelator Fmoc-tyrosine (Fmoc-Y) is probed using particle-tracking microrheology. Gelation is initiated by adding glucono-δ-lactone (GdL), which gradually lowers the pH with time, allowing the dynamic properties of gelation to be examined. Consecutive plots of probe particle mean square displacement (MSD) versus lag time τ are shown to be superimposable, demonstrating the formation of a self-similar hydrogel network through a percolation transition. The analysis of this superposition yields a gel time tgel = 43.4 ± 0.05 min and a critical relaxation exponent nc = 0.782 ± 0.007, which is close to the predicted value of 3/4 for semiflexible polymer networks. The generalized Stokes-Einstein relation is applied to the master curves to find the viscoelastic moduli of the critical gel over a wide frequency range, showing that the critical gel is structurally and rheologically fragile. The scaling of G'/G″ as ω0.795±0.099 ≈ ω3/4 at high frequencies provides further evidence for semiflexible behavior. Cryogenic scanning electron micrographs depict a loosely connected network close to the gel point with a fibrillar persistence length that is longer than the network mesh size, further indications of semiflexible behavior. The system reported here is one of a number of synthetic systems shown to exhibit semiflexible behavior and indicates the opportunity for further rheological study of other Fmoc derivatives.
Langmuir : the ACS journal of surfaces and colloids.Langmuir.2014 Apr 11. [Epub ahead of print]
The viscoelasticity of hydrogel networks formed from the low-molecular-weight hydrogelator Fmoc-tyrosine (Fmoc-Y) is probed using particle-tracking microrheology. Gelation is initiated by adding glucono-δ-lactone (GdL), which gradually lowers the pH with time, allowing the dynamic properties of gel
PMID 24684622

Implications of Changing the Amount of Thickener in Thickened Infant Formula for Infants with Dysphagia.

September C1, Nicholson TM, Cichero JA.Author information 1School of Chemical Engineering, The University of Queensland, Brisbane, QLD, Australia, c.september@uq.edu.au.AbstractWhen a dysphagic infant is prescribed thickened infant formula (TIF) as a treatment method, some clinicians determine their own addition rates of thickener to meet the specific needs of the infant rather than relying on the directions on the tin. In this study the rheological behaviour of a TIF at different addition levels of thickener was measured to determine whether there was a difference in full rheological response and in viscosity. In addition, the time taken for the TIF to reach a near-stable viscosity was also measured. One hundred grams of Karicare® infant formula was made up according to the manufacturer's instructions and Karicare® feed thickener was added at levels of 2, 3, 4, 5, and 6 g, respectively. A strain-controlled rheometer (ARES) with Couette geometry was used to rheologically characterise the TIF at the different levels of thickener addition. There was a significant difference in viscosity between the low levels and the higher levels of addition thickener (p < 0.05). Also, the low levels of thickener addition showed Newtonian-like behaviour, whereas the higher levels of addition were shear-thinning. The time taken for the thickener to reach a near-stable viscosity was found to be 10 min. Guidelines for thickened infant formula need to take into account the different levels of thickener addition rates.
Dysphagia.Dysphagia.2014 Mar 23. [Epub ahead of print]
When a dysphagic infant is prescribed thickened infant formula (TIF) as a treatment method, some clinicians determine their own addition rates of thickener to meet the specific needs of the infant rather than relying on the directions on the tin. In this study the rheological behaviour of a TIF at d
PMID 24658846

Development and Characterization of a Gel Formulation Integrating Microencapsulated Nitrofurazone.

Balcão VM, Santos MG, Martins PR, Chaud MV, Oliveira Junior JM, Tubino M, Vila MM1.Author information 1Laboratory for the Development and Evaluation of Bioactive Substances, University of Sorocaba, Cidade Universitária, Rod. Raposo Tavares km 92.5, CEP 18023-000 Sorocaba, São Paulo, Brazil. marta.vila@prof.uniso.br.AbstractNitrofurazone (NTZ) is usually employed in the topical treatment of infected wounds and lesions of both skin and mucosa. Microencapsulation is a process utilized in the incorporation of active ingredients within polymers aiming at, among other objectives, the prolonged release of pharmaceutical compounds and protection from atmospheric agents (viz. moisture, light, heat and/or oxidation). With the goal of utilizing the microparticles containing encapsulated NTZ in pharmaceutical formulations, one prepared microparticles containing NTZ via ionotropic gelation of sodium alginate. The microparticles were characterized via scanning electron microscopy analyses, Fourier transform infrared spectroscopy (FTIR) analyses, via determination of encapsulation efficiency, and via thermal analyses (both TGA and DSC). The final gel formulation was also characterized rheologically. The extrusion/solidification technique employed to obtain the calcium alginate microparticles with encapsulated NTZ was found to be adequate, and produced an NTZ encapsulation efficiency of ca. 97.8% ± 1.1%. The calcium alginate microparticles thus obtained, with encapsulated NTZ, exhibited an oval shape and hydrodynamic diameters between 500 µm and 800 µm. From the thermal analyses performed, together with information from the infrared spectra, one may conclude that NTZ did not strongly bind to the polymer, which may be favorable for the release of the active ingredient. From the results obtained in the present research effort, one may conclude that the microparticles produced possess the potential to be utilized as carriers for NTZ in pharmaceutical formulations such as gels, ointments, and solutions.
Current pharmaceutical biotechnology.Curr Pharm Biotechnol.2014 Jan 12. [Epub ahead of print]
Nitrofurazone (NTZ) is usually employed in the topical treatment of infected wounds and lesions of both skin and mucosa. Microencapsulation is a process utilized in the incorporation of active ingredients within polymers aiming at, among other objectives, the prolonged release of pharmaceutical comp
PMID 24433503

Japanese Journal

Rheological Characterization of Suspension and Gel Prepared from Colloidal Silica for Sealed Lead-Acid Batteries by Small Amplitude Dynamic Oscillation Measurement

PARK Jin,PARK Seung Bin,YANG Seung-Man,HONG Won Hi,CHOI Chun Rak,KIM Jeong Heon
Journal of chemical engineering of Japan 41(4), 238-245, 2008-04-01
… series) and sulfuric acid, were investigated rheologically by a small amplitude dynamic oscillation measurement method in which storage and loss moduli were monitored with time. …
NAID 10021109970