Percutaneous transluminal angioplasty of the renal artery in transplanted kidneys

The objective of the work was to evaluate the contribution of percutaneous transluminal angioplasty (PTA) to treatment of hypertension and the graft function of a transplanted kidney. Angioplasty of the graft artery was performed in 39 patients. Technical success rate: 85%. Complications: 13%--in particular during the first years after introduction of the method. Twenty seven patients were followed up on a long-term basis. Changes of the median arterial pressure (MAP) were evaluated as well as glomerular filtration (GF) assessed by creatinine clearance. Mean values: [table: see text] A statistically significant (p < 0.01) reduction of the median arterial pressure (drop by > 10 mm Hg) along with reduction of the number of antihypertensive drugs was recorded in 70% of the patients during the first year and in 80% kidney recipients in investigations extending beyond one year. A significant increase of glomerular filtration (by > 20%) was found in 40% of the patients, on average the rise was insignificant. During the follow up period 13 kidney recipients were transferred to a dialyzation programme due to failure of the grafts as a result of rejection. CONCLUSION: Percutaneous transluminal angioplasty of a stenosis of the graft artery is the method of first choice in the treatment of hypertension. It is of fundamental importance also in rare cases in order to preserve or improve graft function and thus delay dialyzation treatment.     

Similarities between lime and limestone in wet—dry scrubbing

Lime is utilized as a sorbent in most commercial wet—dry scrubbing processes for SO₂ control, while limestone is not considered to be sufficiently reactive for such a purpose. Faced with the fact that limestone is potentially the least expensive sorbent for SO₂ control, a study was conducted to uncover ways to increase the reactivity of this sorbent in order to use it in wet—dry scrubbing applications. The study was focused on a comparison of the reactivity of lime and limestone during the dry reaction period. The conditions which have a major impact on the reactivity include the sorption capacity of water vapour, the BET surface area, the relative humidity and the sorbent utilization. The experiments revealed several similarities between the two sorbents, which led to a number of ways to obtain increased limestone acitivity.     

On the investigation of d.c. plasmatron discharges by optical emission spectrometry

We investigated the emission spectra resulting from high rate plasmatron sputtering in order to gain further information on the coating process. The measured relations between the peak intensities of the target material and such plasmatron discharge parameters as discharge current, discharge power and deposition rate were almost linear. However, the intensity showed a strong pressure dependence. In the case of reactive high rate sputtering there is a drastic drop in the spectral line intensity of the target material as the pressure of the reaction gas increases. The behaviour of both the line intensity and the discharge voltage clearly reflects the coverage of the target with reaction products as a function of the pressure ratio p_O2/p_tot. The effects of the residual gas on the metal sputter rate and the desorption of H₂O during r.f. substrate cleaning were verified. From these results it is seen that emission spectroscopy may be used to advantage for monitoring the process of high rate plasmatron sputtering.     

Phagocyte dysfunction in common variable immune deficiency

The history of a 13-year old boy is reported who suffered from frequent bacterial, enteroviral, and protozoal infections since late infancy. A decrease in the serum levels of IgG2, IgG3, IgA, a neutrophil dysfunction, and a partial cellular immune deficiency could be demonstrated. A deficiency of folic acid produced a pancytopenia which enhanced the patient's susceptibility to infections. The combined substitution of gammaglobulins and folic acid only was able to break this vicious cycle.     

Speed-varying ol systems

A new type of L system is introduced in which each rule has a “delay”, a word over some alphabet, associated with it. This results in a new characterization of the etol languages, which only partially carries over to the eol languages.     

Scatter correction of transmission near-infrared spectra by photon migration data: quantitative analysis of solids

The scope of this work is a new methodology to correct conventional near-infrared (NIR) data for scattering effects. The technique aims at measuring the absorption coefficient of the samples rather than the total attenuation measured in conventional NIR spectroscopy. The main advantage of this is that the absorption coefficient is independent of the path length of the light inside the sample and therefore independent of the scattering effects. The method is based on time-resolved spectroscopy and modeling of light transport by diffusion theory. This provides an independent measure of the scattering properties of the samples and therefore of the path length of light. This yields a clear advantage over other preprocessing techniques, where scattering effects are estimated and corrected for by using the shape of the measured spectrum only. Partial least squares (PLS) calibration models show that, by using the proposed evaluation scheme, the predictive ability is improved by 50% as compared to a model based on conventional NIR data alone. The method also makes it possible to predict the concentration of active substance in samples with other physical properties than the samples included in the calibration model.     

Kohlenstoffaktivität und -löslichkeit in austenitischen Chrom-Nickel-Stählen mit rd. 18% Cr

Ermittlung der Löslichkeit für Kohlenstoff und das Ausscheidungsverhalten von Karbiden in Eisen-Kohlenstoff-Legierungen mit rd. 18% Cr in Abhängigkeit vom Nickelgehalt bis zu rd. 40% durch Aufkohlungsversuche in Wasserstoff-Methan-Gemischen bei Temperaturen zwischen 900 und 1200°C. Auswertung der Versuchsergebnisse für Aktivitäts- und Löslichkeitsberechnungen. Röntgenographische Untersuchungen der isolierten Karbide.     

On toxicity question of synthetic polymers and their extracts tested in vitro and in vivo

The increasing use of polymer materials in medicine as much as the undesirable effects observed in patients during their application made us to study not only their functional properties but also their toxicological and biostability parameters, before their clinical application. Some of the aspects of this wide-ranging problem have been studied in our laboratory. Our aim was to try and identify the effect synthetic polymers and their extract have on different biological systems. The comparison of the results obtained through some of the biological methods was aimed at finding out to what extent such methods were suitable for testing of the polymer toxicity on living tissue.     

Network formation involving epoxide and carboxyl groups

Summary The base catalyzed reaction between epoxide and carboxyl groups was studied using a simple model system phenylglycidyl ether-caproic acid in the presence of triethylamine. The reaction was investigated by mass spectrometry and GPC which provide an overall qualitative and quantitative survey of all the forming reaction products. The addition esterification is followed by etherification and condensation esterification and the main reaction product, monoester, is disproportionated yielding diester and diol. In a polyfunctional system, the latter reaction may cause splitting of the polymer chain and formation of new crosslinks.