1.
Cwikiel, Magdalena
(författare)
Pathophysiology of 5-fluorouracil induced cardiotoxicity : a clinical and experimental study
1996
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
This thesis concerns the pathophysiology of 5-fluorouracil (5-FU) induced cardiotoxicity. The aim of the clinical studies was to determine whether hemorheological factors might explain 5-FU cardiotoxicity (I) and if the syndrome was associated with free radical (FR) generation and lipid peroxidation (II). Changes in blood and plasma viscosity, fibrinogen, hematocrit, and thiobarbituric acid-reactive substances (TBARS) were studied in patients with esophageal or head and neck carcinoma during treatment with 5-FU. The study showed a decrease in blood and plasma viscosity, probably caused by a decrease in fibrinogen. Study of TBARS did not support the hypothesis that FRs could be involved in the cardiotoxicity of 5-FU. In the experimental studies in rabbits (III,IV) we examined the early and late, local and systemic effect of 5-FU on endothelium, using scanning and transmission electron microscopic evaluation of small arteries, after in vivo treatment with 5-FU. Perfusion fixation was used. The following parameters were evaluated: vessel wall and endothelial cell (EC) contraction, EC edema, cytolysis, denuded areas, platelet accumulation, fibrin formation. The studies showed severe damage to ECs with accompanying thrombus formation, supporting the hypothesis that the thrombogenic effect of 5-FU, secondary to its direct cytotoxic effect on the endothelium is the pathophysiological mechanism of 5-FU cardiotoxicity. The influence of 5-FU on endothelial cell lines in a cell culture model was studied with regard to DNA synthesis, cell death and release of prostacyclin (V). Methotrexate (MTX), an antimetabolite without cardiotoxic properties, was tested in the same way. (3H)thymidine incorporation, total cellular protein, loss of (3H)thymidine from prelabelled cells, 6-keto-prostaglandin F1* were measured. DNA synthesis decreased significantly and the release of prostacyclin by ECs increased significantly when incubated with 5-FU; this effect was not seen for MTX. The study indicate specific susceptibility of benign EC for 5-FU.
2.
Jernström, Helena
(författare)
Effects of Oral Contraceptives on Endogenous Hormones, Body Constitution, and Breast Epithelium in Healthy, Young Women
1996
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
This thesis concerns the effects of low-dose oral contraceptives (OCs) on endogenous hormones, insulin-like growth-factor-1 (IGF-1), sexual hormone binding globulin (SHBG), and body constitution in two groups of healthy women aged 1925 who had never been pregnant. Prolactin concentrations were elevated in a subgroup of present and former users. IGF-1 concentrations were significantly decreased during menstrual cycle days 1823 in present OC users compared with never users, while no effect was seen during cycle days 510. Former users had significantly higher follicle-stimulating hormone (FSH) concentrations than never users. This rebound-like phenomenon peaked one year after cessation of use. High FSH concentrations could increase the number of ovulations and thereby the ovarian cancer risk, especially among intermittent users who may experience repeated rebound peaks. Among present and former users SHBG concentrations were significantly correlated with reported weight gain in connection with OC start. SHBG was not related to the same hormonal and constitutional parameters in former users as in never users. Breast size was significantly larger in present users than in former and never users, and approximately half of the ever users reported breast tenderness or enlargement in connection with OC start. Breast epithelial proliferation rate was studied by means of a new monoclonal antibody, Ki-S5, in 58 women who had undergone reduction mammoplasties and who were born 1940 or later. There was no significant difference in breast tissue proliferation between present, former and never users. Women who had used OCs before the first full-term pregnancy had a significantly higher proliferation rate in the breast tissue than other women, regardless of present OC status. Women who used exogenous hormones and who had a first and/or second degree relative relative with breast cancer had a significantly higher proliferation rate in the breast tissue than other women. A high proliferation rate may increase the risk of developing breast cancer.
3.
Johnsson, Anders
(författare)
Pharmacokinetic and pharmacodynamic studies on cisplatin in mice and men
1996
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
Methodological tools for studies of the cytostatic agen cisplatin (CDDP) were explored and applied to elucidate various aspects of pharmacokinetics, drug distribution, chemomodulation and pharmacodynamics. An immunohistochemical assay for analysis of CDDP-DNA adducts, i.e. the drug in its probable target position, was modified to allow quantitation with computerized image analysis. The methodological sources of error were estimated. We found the method to be feasible for comparing samples of the same tissue type, stained in the same batch and preferrably measured by one observer on one occasion. The pharmacokinetics were studied as platinum (Pt) and CDDP-DNA adducts in nude mice. The highest tissue concentration was noted in kidney at 15 min. A biphasic elimination of Pt was observed in most sample types and the terminal half-life was similar (55h-76h) in whole-blood, serum, kidney, liver and testis. In brain the pharmacokinetics differed with a gradual accumulation during the study period of 7 days. Peak adduct levels were reached between 30 min and 4h. Each tissue type had its specific adduct staining pattern. With escalating CDDP doses there was a linear increase in both Pt concentrations and CDDP-DNA adducts including tumor. There were also good correlations between serum-Pt, tissue levels of Pt and adducts, respectively. Heterogeneities in the intratumoral drug distribution were described and a model was presented for investigating the potential influence of vascularization and cell proliferation on intratumoral adduct distribution by using different immunohistochemical stainings of parallel sections. A weak correlation was found between adducts and proliferation, which might indicate that drug uptake and adduct formation is increased in proliferating cells. The antifungal agent amphotericin B was given to glioma-bearing rats with the purpose of enhancing the cytotoxicity of CDDP. The combined treatment resulted in excessive nephrotoxicity and in increase levels of CDDP-DNA adducts on kidneys. This indicates that nephrotoxicity is related to adduct formation in kidneys. It also shows that adduct analysis can be a valuable tool for assessing the mechanisms of interaction between CDDP and modulation agents. Ten patients were studies during the first cycle of CDDP-based chemotherapy. With limited-sampling and a population approach useful pharmacokinetic information was obtained. CDDP-DNA adducts in lymphocytes and buccal cells showed different kinetic profiles, possibly due to differences in cell turn-over. Renal damage, studied in terms of urinary protein excretion, was first displayed as tubular damge and later as impaired glomerular barrier function. Significant correlations were found between tubular dysfunction and pharmacokinetic parameters. These results could be the basis for further pharmacodynamic studies aiming towards individualized dose adaptation for cancer chemotherapy.
4.
Garkavij, Michael
(författare)
Improving radioimmunotargeting of tumors : the impact of extracorporeal immunoadsorption and preload in rats
1996
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
In radioimmunotherapy of tumors, uptake of the monoclonal antibody (MAb) used is often too low in relation to its uptake in normal tissues. The purpose of these studies was to improve experimental tumor radioimmunotargeting with (a) extracorporeal immunoadsorption (ECIA), where excess of radiolabeled MAbs circulating in blood is removed, (b) or by preload with unlabeled MAb prior to injection of radiolabeled MAb, (c) or by a combination of these. ECIA based on the avidin-biotin concept enables direct adsorption of radiolabeled and biotinylated MAb from blood and increases the tumor-to-normal tissue (T/N) uptake ratio by reducing background radioactivity in radiosensitive organs. 267 rats (athymic or Brown Norwegian) grafted with human adenocarcinoma or rat colon adenocarcinoma tumors intramuscularly, and beneath the kidney or liver capsule were included in the studies. Of these rats, 82 were subjected to ECIA. Two radioiodinated and biotinylated MAbs, murine L6 or chimeric BR96, were used and evaluated. (I) Using 50 µg dosage of L6, ECIA reduced whole body and plasma activity as well as improved the detectability of subrenal capsule tumors. T/N uptake ratios were increased on average 3 times. (II) The efficacy of ECIA in removing different injected amounts of L6 from plasma was similar. The highest T/N ratios persisting 24h after start of the ECIA were obtained by using 10 µg of 125I-L6-biotin. (III) The efficacy of preload in enhancing tumor uptake and simultaneously decreasing uptake in normal tissues was obtained with 250µg of 125I-L6 preceded by a preload of 50µg unlabeled L6 only. (IV) The effects on radioimmunotargeting of preload and ECIA in combination were synergistic and improved T/N uptake ratios up to 17 times. (V) As compared with ECIA, a new method of whole blood immunoadsorption (WBIA) was technically easier to perform, safer and more reliable, but of approx. comparable efficiency. (VI) WBIA was even applicable on the internalizing and highly tumor selective 125I-BR96-biotin MAb, resulting in manifestly improved T/N ratios.
5.
Elfving, Peter
(författare)
Cytogenetic studies of normal kidney tissue and renal cell carcinoma
1996
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
In the present thesis normal kidney tissue and renal cell carcinoma (RCC) were studied by cytogenetic and fluorescence in situ hybridization (FISH) methods to investigate chromosomal aberrations. In the first study, 4 samples of nonneoplastic kidney tissue were cultured for cytogenetic analysis and trisomy 7 was found in all cases in 3-15% of the cells. In the second study, cytogenetic analysis of 30 RCC showed that +7 was rarely present together with clonal structural abnormalities, in particular 3p changes, making it highly unlikely that trisomy 7 represents a primary change in RCC. In the third study, nonneoplastic kidney tissue was cultured for 4-46 days and the frequency of trisomy 7 showed no consistent variation during the culturing period studied. In the fourth study, FISH of interphase nuclei was performed in uncultured nonneoplastic kidney tissues and showed that the frequency of +7 varied between 1.0-9.0% of the cells. Combination of FISH with immunostaining with CD3 for T-lymphocytes and cytokeratins for epithelial cells showed that, in all samples, the cells with +7 found in nonneoplastic kidney tissue were epithelial in 20-75% and T-lymphocytes in only 0-5%. Among freshly isolated renal cells, in the fifth study, trisomy 7 was observed mainly in proximal tubular cells positive for brush-border antigen, and, to a lesser extent, in distal tubular cells positive for Tamm-Horsfall glycoprotein. The frequency of trisomy 7 in lymphocytes expressing CD3 or CD22 isolated from nonneoplastic and tumor tissues was substantially lower than in the epithelial cells and was not increased compared with the frequency in control lymphocytes from peripheral blood. These results thus demonstrate that the nonneoplastic kidney cells with trisomy 7 are mainly of epithelial origin, preferentially of the proximal tubule. In the final study, 50 consecutive patients with RCC were followed for a median of 4.2 years. There was a significant association between the degree of cytogenetic complexity and survival, in that patients with five or less aberrations had a better prognosis than those with more than five changes. Patients with del(8p)/-8, +12, and +20 had a significantly worse prognosis compared with those without these aberrations, but +7 had no impact on prognosis.
6.
7.
Ahlman, Håkan, 1947, et al.
(författare)
En "ny" tumörmarkör.
1996
Ingår i: Klinisk Kemi i Norden, 8.. - Göteborg. ; , s. 45-52
Bokkapitel (övrigt vetenskapligt/konstnärligt)
8.
Yeung, Moorix Mo-Wai
(författare)
Specific and nonspecific immune mechanisms in human gut : a comparative study of normal and ulcerative colitis intestine
1996
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
The intestine, with its large mucosal surface area, digests and absorbs food nutrients and maintains a beneficial microbial flora in the colon. Local protective immune responses against intestinal pathogens ensure the survival of the individual. These immune reactions are both specific and non-specific in nature. The intestinal epithelium is single-layered and constantly renewed with differentiating epithelial cells moving from the crypt to the luminal surface. Intraepithelial lymphocytes (IEL) are interspersed between the epithelial cells. Ulcerative colitis (UC) is a life-threatening chronic inflammation affecting colon.In this study three molecules belonging to the carcinoembryonic antigen (CEA) family, namely CEA proper, nonspecific cross-reacting antigen 50/90 (NCA 50/90) and biliary glycoprotein (BGP), were found to be specifically localized to the apical surface of colonic epithelial cells. Full expression of these molecules occurs when the cells reach the upper 1/3 of the crypts and are maintained on the mature cells at the luminal surface. Ultrastructurally, CEA, NCA50/90 and BGP are localized to microvesicles and microfilaments of the fuzzy coat/glycocalyx as well as to the microvilli of the epithelial cells. Their unique localization and documented bacterial binding capacities suggest that they have a role in innate immunity.Functional analysis of IEL in normal jejunum, ileum and colon revealed that IEL are in vivo activated T-lymphocytes expressing mRNA for the cytokines IL-1β, IL-2, IL-8, IFNγ and TNFα and that jejunal IEL have T-cell receptor (TCR)/CD3 dependent cytolytic capacity. As many as 10% of IEL actively produce IFNγ. CD4+TCRαβ+IEL, CD8+TCRαβ+IEL and CD4-CD8-TCRαβ+IEL all had a TH1/cytotoxic cytokine profile. IEL could be further stimulated in vitro to express IL-10, TNFβ and TGFβ1, to proliferate and to secrete IFNγ. Thus, active protection and/or regulation of the epithelium via cell-mediated immune reactions are prominent in the gut.UC colon was characterized by a marked lymphocyte infiltration in the lamina propria, 10-50 times the normal level. Most lymphocytes were present in follicle-like cell aggregates containing both T- and B-cells. An unexpected finding was that γδT-cells constituted about 15% of the cells in the aggregates. Such cells are only found intraepithelially in normal gut. γδT-cells of both the intestinal- (TCR-Vδ1/Vγ8) and blood type (TCR-Vδ2/Vγ9) were seen. T-cells in UC colon were activated but nonproliferating and had a down-regulated TCR/CD3 complex. RT-PCR and quantitative immunohistochemistry for cytokine mRNA (n=11) and protein respectively, revealed that the T-cells in UC colon did not produce IL-2, in marked contrast to T-cells in normal colon and to ileal T-cells from UC patients. This was a selective defect since TNFα, IFNγ, IL-1β, IL-8 and TGFβ1 were similarly expressed in normal colon. No TH2 cytokines were seen. Lamina propria leukocytes in UC colon expressed IL-6, a cytokine not found in normal colon. The epithelial cells of UC colon were activated expressing MHC class II antigens, heat shock proteins and the co-stimulatory molecule B7.1/CD80.Our study demonstrates that UC is an immunological disease. The immunopathological picture seen in UC colon probably reflects an inappropriate down-regulation of local immune responses perhaps due to a selective loss of the key cytokine IL-2 in a situation of extreme antigenic stress.
9.
Carlén, Birgitta
(författare)
Electron Microscopy in Diagnostic Pathology with Reference to Mesenchymal Tumors
1996
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
The experience acquired over a period of 15 years of diagnostic electron microscopy of fine needle aspirates and surgical specimens constitutes the base for this thesis. Some of the tumors analyzed represent rare soft tissue tumors, and consequently not very often ultrastructurally described. In locations where sarcomas are rare and unexpected, electron microscopy may contribute to a correct tumor classification when type specific structures are present. Electron microscopic examination is a suitable method to confirm presence of mesenchymal tumor cells in cultures and to compare the morphology in cultures and fresh tumor tissue provided that the ultrastructural features are specific for the tumor in question. Fine needle aspiration together with the use of electron microscopy is a reliable combination in the typediagnosis of small round cell malignant tumors of childhood and adolescence and spindle cell tumors as peripheral nerve sheath tumors, leiomyosarcoma and synovial sarcoma, especially of the monophasic variant. Electron microscopy contributes to the understanding of successive morphologic changes in the dermal microvasculature of Kaposi´s sarcoma. This thesis presents examples that highlight the value of electron microscopy in the multidisciplinary management of musculoskeletal tumors.
10.
