Loss of heterozygosity in cultured human tumor cell lines

One hundred and thirty-seven cultured human tumor cell lines derived from Caucasian patients were surveyed for ten of their polymorphic enzyme phenotypes. The gene frequencies in this cell line population were similar to those of normal Caucasian populations, although consistent differences in phenotype frequencies were detected at each of the loci. All 10 loci showed fewer heterozygous phenotypes and a correspondingly greater number of the common and rare homozygous phenotypes than occur in normal Caucasian populations. On the average, only 85% of the loci expressed in fully differentiated diploid cells were expressed in the neoplastic cell lines adapted to in vitro growth. There was no significant difference in the proportion of loci expressed in cells that had been passaged less than 10 times and in cells passaged more than 50 times. Consequently, it appears that there is a loss of expression in genetic marker loci from at least six different chromosomes. This loss occurs either in the in vivo tumor or in the very early stages of the cultivation of neoplastic cells derived from solid human tumors. Once the cells have become adapted to growth in vitro, the patterns of expression in their polymorphic loci remain stable for many passages.     

Scintigraphic control of pulmonary embolism

Pulmonary embolism was diagnosed by combined perfusion and ventilation scintigraphy in 30 patients. A control examination 6 months later revealed pulmonary embolism or infarction in 8, in spite of conventional treatment. Therefore, patients treated for pulmonary embolism should be reexamined 3 to 6 months after diagnosis.     

Bone and joint tuberculosis in Denmark

Epidemiologic data on 100 patients with bone and joint tuberculosis reported in Denmark from 1980 to 1984 are presented. The annual incidence of skeletal tuberculosis remained unchanged during the period, although most other forms of tuberculosis showed a decreasing trend. Eighteen per cent of all the cases of bone and joint tuberculosis were found among young first generation immigrants, notably from Asia. In the native Danish population, bone and joint tuberculosis was almost exclusively found among the elderly. The lesions were most common in the spine and hip. Thirty per cent of the patients had a previous history of pulmonary tuberculosis.     

Quantitative renal scintillation camera studies in renal transplantation

Renal transplant recipients and donors were studied serially with quantitative renal scintillation camera studies utilizing ¹³¹I-Hippuran and ^99mTc-Iron ascorbate. This study allows for determination of effective renal plasma flow (ERPF), glomerular filtration rate (GFR), filtration fraction (FF), and predicted return in ten minutes. A drop in FF occurred with, or preceded clinical rejection; whereas, an increase in FF occurred with acute tubular necrosis (ATN) caused by preservation injury, aminoglycosides, and following acute rejection. Combined with the other parameters of renal function determined by this technique, FF alternation proved useful in the differentiation of ATN from rejection and in predicting the prognosis of renal homografts.