Determination of mandelic acid enantiomers in urine by gas chromatography and electron-capture or flame ionisation detection

A sensitive and stereospecific GC method was developed for the analysis of R- and S-enantiomers of mandelic acid (MA) in urine, using a chiral CP Chirasil-Dex-CB column. The enantiomers of MA were derivatised with isopropanol into their corresponding isopropyl esters and determined either directly with flame ionisation detection (FID) or after subsequent derivatisation of a hydroxy group with pentafluoropropionic anhydride with electron-capture detection (ECD). Both derivatisation steps proceeded with negligible inversion of enantiomers (<1%). The limit of detection of the FID determination was 8 and 5 mg/l for R-MA and S-MA, respectively and of the ECD determination 1 mg/l for both enantiomers. Repeatability (within-day precision) and reproducibility (day-to-day precision) was for both enantiomers below 7.5% for the FID and below 5.8% for the ECD analysis. The method was applied to urine of volunteers exposed to 105 and 420 mg styrene/m3 air. In the urine of the exposed volunteers, the S-enantiomer showed higher excretion compared to that of the R-enantiomer, with marked interindividual differences in excretion of both enantiomers.     

Cytokines in patients with lung cancer

Lung cancer is one of the most common malignant diseases and is amongst the leading causes of death. Cell-mediated immune response and cytokines could play an important role in antitumour immunity. The aim of the study was to evaluate the cytokines', tumour necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and IL-6, releasing capacity in patients with lung carcinoma and benign lung disease. A group of 41 patients were tested for the production of TNF-alpha, IL-1beta and IL-6 in bronchoalveolar lavage (BAL) and blood. The levels of cytokines in the lung cancer patients were: (1) in BAL - IL-6, 173 +/- 85 pg/ml; TNF-alpha, 170 +/- 116 pg/ml; and IL-1beta, 473 +/- 440 pg/ml; (2) in the blood - IL-6, 197 +/- 53 pg/ml; TNF-alpha, 311 +/- 202 pg/ml; and IL-1beta, 915 +/- 239 pg/ml. Alveolar macrophages of the patients with a lung cancer secreted significantly more cytokines, IL-6 (P = 0.0004) and IL-1beta (P = 0.0047), than alveolar macrophages of the patients with a nonmalignant lung cancer. However, significantly lower levels of cytokine production by the BAL cells were found in patients with small cell lung cancer. This production decreased further in phase IV of nonsmall cell lung cancer.     

Malignant lymphoma of the stomach in association with inflammatory myofibroblastic tumor of the spleen. A case report

We report on a case of a 40-year-old male patient who underwent a gastrectomy because of a biopsy-proven large B-cell lymphoma of the stomach. On surgery, a nodule in the spleen also was noted. Grossly and microscopically, the two lesions were different: the tumor of the stomach appeared white-gray on the cut surface and was a centroblastic variant of diffuse large B-cell lymphoma. Histologically, one perigastric lymph node was involved. Grossly, the splenic nodule was gray-yellow and had a histological appearance of an inflammatory myofibroblastic tumor (IMT). The association between malignant tumor and IMT is rare. In such an association, the latter lesion most often has been reported in the spleen. As EBV may be involved in the genesis of both lymphoma and IMT, we tested both lesions for its presence using in situ hybridization, but the tests were negative. It remains to be verified whether the association between lymphoma and IMT is more than fortuitous.     

Pulmonary embolism after minor elective orthopedic procedure

The occurrence of pulmonary embolism, in spite of thromboprophylaxis after a minor elective orthopedic surgery (release of m. rectus femoris tendon) is reported. In case of this severe complication, an early diagnosis is of outmost importance to enable optimal therapy introduction. Deep vein thrombosis and pulmonary embolism are frequent complications after total joint replacement, however, they may also develop after minor surgical orthopedic procedures. The possible causes of pulmonary embolism after release of m. rectus femoris tendon included the history of varicose veins and sclerozation of calf veins, and operative procedure with intraoperative pressure upon large veins of the iliofemoral region, which may and is expected to occur during this procedure. The importance of thrombopropylaxis in orthopedic surgical procedures is emphasized by this case presentation.