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Abstract  

For the system liquid anion-exchanger—Cr(III)−NCS, an investigation has been made of the dependence of the percentage extraction of Cr(III) on parameters such as standing time of the Cr(III)−NCS solution, temperature, pH and type of exchanger. Quantitative extraction of e.g. 4·10−4 M Cr(III) by 0.1M Aliquat in CCl4 is easily achieved at room temperature, using 4.75M KNCS−0.05N HCl as aqueous phase. At high Cr(III) concentrations, the complex anion present in the organic phase is Cr(NCS) 6 3− ; when working with dilute metal ion solutions, the species extracted is Cr(NCS)4 (H2O) 2 . Separations of mixtures containing 10−2−10−4 M Co(II), Ni(II) and Cr(III) have successfully been accomplished.

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Abstract  

An investigation has been made on the system liquid anion-exchanger-Cd(II)-NCS. The influence of the acidity and thiocyanate concentration of the aqueous phase on the extraction has been studied. Using various methods of analysis, it has been shown that the complex anion present in the organic extracts is Cd(NCS) 4 2− . Details are given concerning the removal of traces of Zn(II) from Cd(II)-containing solutions, and the quantitative separation of Cd(II) from Cr(III).

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Acta Veterinaria Hungarica
Authors:
L. Kóbori
,
T. Németh
,
B. Nemes
,
G. Dallos
,
P. Sótonyi Jr.
,
I. Fehérvári
,
A. Patonai
,
M. J. H. Slooff
,
J. Járay
, and
K. P. De Jong

Hepatic artery thrombosis is a major cause of graft failure in liver transplantation. Use of donor interponates are common, but results are controversial because of necrosis or thrombosis after rejection. Reperfusion injury, hypoxia and free radical production determinate the survival. The aim of the study was to create an 'ideal' arterial interponate. Autologous, tubular graft lined with mesothelial cells, prepared from the posterior rectus fascia sheath, was used for iliac artery replacement in eight mongrel dogs for six months under immunosuppression. Patency rate was followed by Doppler ultrasound. Eight grafts remained patent and another two are patent after one year. The patency rate was good (median Doppler flow: 370 cm/sec) and there was no necrosis, thrombosis or aneurysmatic formation. The grafts showed viable morphology with neoangiogenesis, appearance of elastin, smooth muscle and endothelial cells. Electron microscopy showed intact mitochondrial structures without signs of hypoxia. Tissue oxygenation was good in all cases with normal (< 30 ng/ml) myeloperoxidase production. In conclusion, this autologous graft presents good long-term patency rate. Viability, arterialisation and low thrombogenicity are prognostic factors indicating usability of the graft in the clinical practice without the risk of rejection. Further investigations such as cell cultures and standardisation are necessary.

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Acta Veterinaria Hungarica
Authors:
L. Kóbori
,
G. Dallos
,
Anette S. H. Gouw
,
Tamás Németh
,
B. Nemes
,
I. Fehérvári
,
A. M. Tegzess
,
M. J. H. Slooff
,
K. P. De Jong
, and
F. Perner

Vascular complications in liver transplantation are a major cause of graft failure and mortality. The aim of the study was to create autologous vascular graft without risk of rejection. Posterior rectus fascia sheath lined with peritoneum was used for iliac artery replacement in seven mongrel dogs. The patency was followed by palpation and Doppler ultrasound. The grafts were removed after one month. Five grafts remained patent. The Doppler showed good, relatively increased flow (median flow rate: 383 cm/sec) after one month in all of the cases. Slight increase in diameter was present in all cases. By microscopy the five patent grafts showed viable morphology, fibroblasts, smooth muscle cells and thin fibrin layer in the wall. The grafts were lined partially with a neoendothelial monolayer and a thin fibrin layer. In conclusion, this graft presents an acceptable patency rate and low thrombogenicity, and could be useful in transplantation. Further investigations are needed to study the effect of immunosuppression and rejection on long-term morphology and patency of the grafts.

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