Rheumatoid arthritis, relapsing polychondritis, and pyoderma gangrenosum evolving into non-Hodgkin's lymphoma.

In human beings, the function of the immune system and of inflammation is to protect the individual against invading organisms such as bacteria, viruses, parasites, and fungi as well as thermal and mechanical injuries. The inflammatory process, initiated to destroy foreign organisms or an inappropriate immune response/target tissue, may lead to injury, the destruction of host tissue, and the development of the disease process. This article describes the history of a patient with four disorders of unknown cause, all of which may have evolved from one immunologic aberration.

On the modulating effects of temperature, albumin, pH and calcium on the free fractions of phenobarbitone and phenytoin.

The effects of temperature, albumin, pH and Ca2+ on the binding of phenobarbitone and phenytoin to human serum albumin in buffer have been investigated using equilibrium dialysis. The free fractions of both anticonvulsants were much increased by raising the temperature. Lower free fractions were observed by increasing the albumin concentration from 5-8 g litre-1 and by raising pH from 6 to 9. No significant effect on the free fractions was observed by changing (at pH 7.4) the Ca2+ concentration from 0 to 5 mM. The observed differences in free fractions at 37 degrees C, as determined in phosphate, borate and Krebs-Ringer buffer at pH 7.4, indicate that great care is needed in the choice of dialysis fluid for dialysis of clinical samples.

Comparison of equilibrium dialysis, ultrafiltration, and gel permeation chromatography for the determination of free fractions of phenobarbital and phenytoin.

In this study, three techniques for measuring the free fractions of phenobarbital and phenytoin were compared: equilibrium dialysis, ultrafiltration, and the Hummel and Dreyer method for gel permeation chromatography. In their therapeutic range (15-40 and 10-20 mg/L, respectively) the free fractions of phenobarbital and phenytoin were independent of the drug concentrations. Free fractions of phenobarbital as determined by equilibrium dialysis, ultrafiltration, and gel permeation chromatography were 58.7 +/- 1.8, 58.3 +/- 1.5, and 55.1 +/- 1.7%, respectively. Free fractions of phenytoin were 18.1 +/- 1.1, 17.0 +/- 2.1, and 19.4 +/- 1.2%, respectively. On lowering the albumin concentration, a similar increase in the free fractions of both drugs was observed with all three techniques. The results of this study show that all three techniques are suitable for the determination of free fractions of phenobarbital and phenytoin. Moreover, these techniques seem to be suitable for the investigation of physiological factors that may influence albumin drug binding.

Fibromuscular hyperplasia of the brachial artery--failure of calcium antagonist therapy.

Fibromuscular dysplasia (FMD) of the arteries of the extremities has been reported few times in the literature. The clinical significance of FMD relates to the consequences of interruption of arterial blood to the tissues. We report here the second case of FMD of the brachial artery and discuss the failure of the calcium channel blocker, nifedipine, in the therapy of this disorder. A review of the pertinent literature is included.

Qualitative and quantitative analysis of some synthetic, chemically acting laxatives in urine by gas chromatography-mass spectrometry.

A method for the qualitative and quantitative simultaneous analysis of dioxyanthraquinone, desacetyl-Bisacodyl, phenolphthalein and Oxyphenisatin in human urine using gas chromatography-mass spectrometry (GC-MS) has been developed. The compounds were extracted from urine at pH 7.5 with diethyl ether using Extrelut extraction columns, followed by evaporation and trimethylsilylation. The method used electron beam ionization GC-MS employing a computer-controlled multiple-ion detector (mass fragmentography). The recovery from urine for the various compounds was between 80% and 100%. The detection limit for these compounds was in the range 0.01--0.05 micrograms/ml of urine. The method proved to be suitable for measuring urine concentrations for at least four days after administration of a single oral low therapeutic dose of the laxatives to sixteen healthy volunteers.

Quantitation with high-performance thin-layer chromatography and programmed multiple development with high-performance micro-thin-layer material for drug analyses in biological fluids.

The programmed multiple development thin-layer chromatography (PMD-TLC) technique was compared with the conventional chromatographic technique on both normal and HPTLC plates. The potency of this high-performance TLC is illustrated and discussed by means of the data obtained with the determination of digitoxin in human serum. Improvement of the efficiency of TLC, resulting in a better resolution and sensitivity with PMD-TLC using using HPTLC plates, makes this high-performance TLC technique comparable to high-performance liquid chromatography. This TLC approach might lead to a sensitive, rapid, selective and simply assay for routine serial analyses and, because of its specificity and flexibility, it may facilitate drug interaction studies.

Quantitative gas chromatographic analysis of flunitrazepam in human serum with electron-capture detection.

A rapid method for the determination of flunitrazepam and desmethylfflunitrazepam in human serum in the range 10-300 ng/ml is described. Both drugs are isolated from biological material by means of a single extraction, part of the organic phase is evaporated to dryness and the residue is dissolved in a small volume of benzene. Without further purification, the substance is determined gas chromatographically with an electron-capture detector configuration of 63Ni-type. The method permits the quantitative determination of at least 25-300 ng/ml with an overall recovery of flunitrazepam of 99.7 +/- 4.9% and of desmethylflunitrazepam of 98.6 +/- 7.8% from serum. All calculations were carried out by a data system that was programmed for this purpose. The limit of detection for flunitrazepam is of the order of 1 ng/ml in serum. The method is sufficiently sensitive and specific for therapy control purposes. The time needed for an analysis is less than 1 h.