Establishment and characterization of human B-lymphocytic lymphoma cell lines (BALM-3, -4 and -5); intraclonal variation in the B-cell differentiation stage.

This study describes the establishment of three non-Burkitt B-lymphoma cell lines (BALM-3, BALM-4 and BALM-5) originating from the pleural effusion of a patient with a poorly differentiated diffuse lymphocytic lymphoma. The cells of BALM-3, -4 and -5 exhibited a number of properties which distinguish them from the usual B-cell type lymphoblastoid cell lines. Thus, they lacked the Epstein-Barr virus genome and had abnormal chromosome constitutions including a 14q+ marker. The presence of the identical surface immunoglobulin isotypes (gamma and chi chain determinants), and Ia-like B-cell-associated antigen in the cultured cells and in the "fresh" lymphoma cells in vivo was demonstrated. These findings strongly suggested that these cell lines have B-cell characteristics and were derived from the original tumor cell population. BALM-5 cells, however, showed somewhat different growth, cell surface marker profile and functional characteristics compared to those of BALM-3, and -4 cells. These variations suggest that the BALM-5 cells were probably at different stages of B-cell maturation than those of BALM-3 and -4, even though all three cell lines (established in three separate flasks) originated from the cells of the same pleural effusion of a lymphoma with monoclonal B-cell characteristics.     

Development of renal cell carcinoma in living donor kidney grafts

BACKGROUND: Although development of malignancies after transplantation is well recognized, de novo development of cancer in renal transplants is a rare phenomenon. We describe two cases of de novo development of renal cell carcinoma in two living donor grafts. MATERIALS AND RESULTS: The recipients were 45 and 4 years, respectively, at transplantation and their fathers were donors. Because of failure to grow, they were both treated with human growth hormone. Over the years a number of cysts developed in the grafts and after 8 and 7 years the echogenecity of some of the cysts changed. Biopsy confirmed the diagnosis renal cell carcinoma 9 and 11 years after transplantation. The grafts were removed and the immunosuppressive therapy discontinued. The two fathers are well with normal function of the native kidney and no signs of cyst formation or cancer. CONCLUSION: Two cases of de novo development of cancer in living donor kidney transplants are described. Because a stimulatory effect of growth hormone on tumor genesis has been described, this treatment may have been of importance in the tumor development. The findings emphasize the importance of annual ultrasonographic surveillance of renal grafts, especially in the pediatric population.     

Using fMRI to quantify the time dependence of remifentanil analgesia in the human brain.

To understand and exploit centrally acting drugs requires reliable measures of their time course of action in the human brain. Functional magnetic resonance imaging (fMRI) is able to measure noninvasively, drug-induced changes in task-related brain activity. Here, we have characterized, in a specific region of the brain, the time of onset of action and the half-life of action of a clinically relevant dose of a potent opioid analgesic agent, remifentanil. These times were established from the temporal variation of the amplitude of the blood oxygen level-dependent response in the insular cortex contralateral to a painfully hot thermal stimulus, in volunteers receiving a remifentanil infusion. The insular cortex has repeatedly been reported as activated by noxious thermal stimulation. The times of onset and offset of drug action were each characterized by a half-life for changes in fMRI signal from within the insula. These characteristic times agreed with the observed drug-induced analgesia and previous pharmacokinetic-pharmacodynamic measurements for remifentanil. We have successfully measured, for the first time using fMRI, temporal pharmacological parameters for a CNS-active drug based on its effect on task-related activity in a specific brain region. Comparison of the time course of regional brain activity with pain perception could reveal those regions engaged in drug-induced analgesia.     

The impact of CYP2C9 genetics and oral contraceptives on cytochrome P450 2C9 phenotype.

CYP2C9-dependent drug metabolism is subject to large interindividual variation. To some extent, this is explained by genetic polymorphism with expression of enzyme variants that differ in catalytic activity. The aim of this study was to characterize the variation in CYP2C9 phenotype in relation to genotype, with further analysis of the CYP2C9 gene in metabolic outliers. A study population of 126 healthy white subjects were recruited and genotyped for the variant alleles, CYP2C9*1-3. In CYP2C9 phenotyping with losartan, three subpopulations were distinguished that differed in the number of CYP2C9*3 alleles (0, 1, or 2). A three-fold higher metabolic ratio (MR; urinary losartan/carboxymetabolite) was found comparing CYP2C9*1/*3 (n = 20) to CYP2C9*1/*1 (n = 81), but there was considerable variation within each genotype. Subjects genotyped as CYP2C9*1/*1, but with an unexpectedly slow oxidation of losartan, were selected for DNA-sequencing analysis of the CYP2C9 gene. Interestingly, single nucleotide polymorphisms (SNPs) could not be identified either in the 5'-flanking region, the nine exons, or exon-intron boundaries. However, sequencing of the CYP2C9 gene was also carried out in patients genotyped as CYP2C9*1/*1 but with an exceptionally low steady-state clearance of S-warfarin. Here, five different SNPs were identified. In further analysis of the healthy volunteers, it became evident that women on oral contraceptives (OCs) had slower oxidation of losartan (MR of losartan: 1.7) than women without OCs (MR of losartan: 0.86). This novel finding was not explained by a different frequency of variant alleles. In summary, CYP2C9 genotype and oral contraceptives both contribute to a large interindividual variation in CYP2C9 activity.