1.A Biomechanical Comparison between Taylor’s Spatial Frame and Ilizarov External Fixator
BB Tan ; R Shanmugam ; YP Chua ; Hossain G ; A Saw
Malaysian Orthopaedic Journal 2014;8(2):35-39
Taylor’s spatial frame (TSF) and Ilizarov external fixators
(IEF) are two circular external fixator commonly used to
address complex deformity and fractures. There is currently
no data available comparing the biomechanical properties
of these two external fixators. This study looks into the
mechanical characteristics of each system. TSF rings with
6 oblique struts, 4 tube connectors, 4 threaded rods, and
6 threaded rods were compared to a standard IEF rings
with 4 threaded rods. Compression and torsional loading
was performed to the frame as well as construct with
Polyvinylchloride tubes. TSF rings with 4 tube connectors
had the highest stiffness (3288 N/mm) while TSF rings
with 6 struts was the least stiff. The situation was reversed
for torsion where TSF rings with 6 oblique struts had the
highest torsional stiffness (82.01 Nm/Degree) and frame
Ilizarov rings with 4 threaded rods the least. Standard TSF
construct of two ring with 6 oblique struts have better
torsional stiffness and lower axial stiffness compared to
the standard IEF.
Ilizarov Technique
3.Zanamivir Oral Delivery: Enhanced Plasma and Lung Bioavailability in Rats.
Srinivasan SHANMUGAM ; Ho Taek IM ; Young Taek SOHN ; Kyung Soo KIM ; Yong Il KIM ; Chul Soon YONG ; Jong Oh KIM ; Han Gon CHOI ; Jong Soo WOO
Biomolecules & Therapeutics 2013;21(2):161-169
The objective of this study was to enhance the oral bioavailability (BA) of zanamivir (ZMR) by increasing its intestinal permeability using permeation enhancers (PE). Four different classes of PEs (Labrasol(R), sodium cholate, sodium caprate, hydroxypropyl beta-cyclodextrin) were investigated for their ability to enhance the permeation of ZMR across Caco-2 cell monolayers. The flux and Papp of ZMR in the presence of sodium caprate (SC) was significantly higher than other PEs in comparison to control, and was selected for further investigation. All concentrations of SC (10-200 mM) demonstrated enhanced flux of ZMR in comparison to control. The highest flux (13 folds higher than control) was achieved for the formulation with highest SC concentration (200 mM). The relative BA of ZMR formulation containing SC (PO-SC) in plasma at a dose of 10 mg/kg following oral administration in rats was 317.65% in comparison to control formulation (PO-C). Besides, the AUC0-24 h of ZMR in the lungs following oral administration of PO-SC was 125.22 +/- 27.25 ng hr ml(-1) with a Cmax of 156.00 +/- 24.00 ng/ml reached at 0.50+/-0.00 h. But, there was no ZMR detected in the lungs following administration of control formulation (PO-C). The findings of this study indicated that the oral formulation PO-SC containing ZMR and SC was able to enhance the BA of ZMR in plasma to an appropriate amount that would make ZMR available in lungs at a concentration higher (>10 ng/ml) than the IC50 concentration of influenza virus (0.64-7.9 ng/ml) to exert its therapeutic effect.
Administration, Oral
;
Animals
;
Biological Availability*
;
Caco-2 Cells
;
Humans
;
Influenza, Human
;
Inhibitory Concentration 50
;
Lung*
;
Orthomyxoviridae
;
Permeability
;
Plasma*
;
Rats*
;
Sodium
;
Sodium Cholate
;
Zanamivir*