| 21. |
- Johnsson, Anders
(författare)
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Pharmacokinetic and pharmacodynamic studies on cisplatin in mice and men
- 1996
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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.
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| 22. |
- Knutson, Folke
(författare)
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The quality of red blood cells and platelets intended for transfusion : Opportunities for improvements
- 1999
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A new, automated technique for collection and instant preparation of blood components has been developed. The device enables the combined collection of red cells (250 mL) and plasma (475 mL). No adverse effects were seen in the donors. The blood components were of good quality. The impact of the pre-separation temperature on whole blood was studied in two studies. In the first study blood was collected and put into stoppered test tubes. The test tubes were then put into water bath at 15,20,25 and 30 °C. Samples were taken at intervals during 24 hours. The lactate concentration increased and 2,3-DPG concentrations decreased during storage and at a higher rate with higher temperature. In the second study blood was collected and dived into half units. One half unit was actively cooled to 20 °C the other half kept at 28 °C. Blood component preparation was done after 6 hours. There were a significant change in 2,3-DPG, pH and lactate already after two hours hold of the whole blood. The differences were maintained for one week and for 2,3-DPG throughout 28 days storage. Myeloperoxidase levels in plasma were lower in the cooled units. The leucocytes reduction properties of BAT procedure were improved by addition of mannitol in the anticoagulant. The contents of leucocytes in RBC units were in the test group 32x106 and in the control group 573x106. In vitro storage data showed no significant difference between the two groups during 42 days of storage of the red cells. A photochemical treatment (PCT) process has been used in decontamination of buffy-coat derived platelets (BC-PCs). Different strains of bacteria known to be associated with bacterial contamination's of blood components were added to two pooled ABO matched BC-PCs. After mixing the BC-PCs were divided. One BC-PC underwent PCT and the other did not. All bacterial experiments were made in duplicates. In all experiments, the bacteria were killed except in one with Bacillus cereus, a known spore former. PCT conditions similar to those used in the bacterial inactivation experiment were efficacious to inactivate HIV-1. In a second study a number of in vitro parameters known to be related to viability or function of stored platelets were tested. No physiologically relevant differences were found between the test and the control BC-PCs during 7 days of storage.
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| 23. |
- Larsson, Gunnel, et al.
(författare)
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Importance-satisfaction discrepancies are associated with health-related quality of life in five-year survivors of endocrine gastrointestinal tumours
- 1999
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Ingår i: Annals of Oncology. - 0923-7534 .- 1569-8041. ; 10:11, s. 1321-1327
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Tidskriftsartikel (refereegranskat)abstract
- Background: Little is known about the health-related-quality of life (HRQoL) of patients with endocrine gastrointestinal tumours. In this study, HRQoL was investigated in long-term survivors of endocrine GI tumours. Patients and methods: A questionnaire including the EORTC QLQ-C30 and ratings of importance of and satisfaction with a variety of HRQoL aspects was mailed to patients with carci-noid tumours (n = 64), or endocrine pancreatic tumours (EPT, n = 55). Median time since diagnosis was 120 months (range 60–360). The majority of patients (77 of 119) had ongoing treatment. Results: The EORTC QLQ-C30 ratings suggest that in spite of a long disease duration and treatment, patients perceived their HRQoL as relatively good. There were no major differences in HRQoL ratings between patients with carcinoid tumours and those with EPT. Patients whose ratings of importance was higher than their ratings of satisfaction with a specific HRQoL aspect also evidenced a low HRQoL for that aspect. Conclusions: The results indicate that survivors of endocrine GI tumours enjoy a relatively good HRQoL and suggest that importance < satisfaction discrepancies identify patients with a low quality of life.
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| 24. |
- Ding, W Q, et al.
(författare)
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Effects of ethanol on muscarinic receptor-stimulated c-fos expression in human neuroblastoma cells
- 1997
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Ingår i: Brain Research. Molecular Brain Research. - 0169-328X. ; 46:1-2, s. 77-84
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Tidskriftsartikel (refereegranskat)abstract
- The effect of ethanol exposure on muscarinic receptor-stimulated expression of c-fos was investigated in SH-SY5Y cells. Four days of ethanol exposure enhanced carbachol-stimulated c-fos mRNA expression, analyzed with Northern blot, and Fos/AP-1 binding activity, measured with gel mobility super shift assay. Pre-incubation with muscarinic antagonists or the protein kinase C inhibitor GF109203X demonstrated that, in both control and ethanol-treated cells, carbachol-induced c-fos expression was mediated via muscarinic M1 receptors and to a large extent through protein kinase C. However, phorbol ester-induced c-fos expression was unaffected in ethanol-treated cells. Acute exposure to ethanol caused a suppression of both carbachol- and phorbol ester-stimulated c-fos expression. These results demonstrate that muscarinic receptor-stimulated gene expression is sensitive to both acute and long-term ethanol exposure.
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| 25. |
- Kölby, Lars, 1963, et al.
(författare)
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Somatostatin receptor subtypes, octreotide scintigraphy, and clinical response to octreotide treatment in patients with neuroendocrine tumors.
- 1998
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Ingår i: World journal of surgery. - 0364-2313. ; 22:7, s. 679-83
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Tidskriftsartikel (refereegranskat)abstract
- Several types of neuroendocrine tumor express high numbers of somatostatin receptors (sstr). We have compared the expression of sstr subtypes with the outcome of octreotide scintigraphy in patients with carcinoids and medullary thyroid carcinoma (MTC) in comparison with Hürthle cell tumors. The effect of sstr activation (octreotide treatment) on tumor markers was also studied in patients with disseminated carcinoid tumors. Six patients with carcinoid tumors (four midgut and two foregut), and three patients with thyroid tumors (one MTC, one Hürthle cell carcinoma, and one Hürthle cell adenoma) were studied. Octreotide scintigraphy visualized tumor sites in all nine patients. Macroscopic tumor was verified at these sites at subsequent surgical exploration. Using Northern blotting and subtype-specific riboprobes, sstr could be detected in all tumors examined. All five sstr subtypes were detected in most of the carcinoid tumors. All six carcinoids expressed sstr2. This was in contrast to the findings for the thyroid tumors analyzed, which also expressed several sstr subtypes but in some cases lacked expression of sstr2. This was also the case for normal thyroid tissue. Clinically, octreotide treatment of the patients with midgut carcinoid tumors resulted in palliation of hormonal symptoms accompanied by a significant reduction of urinary 5-HIAA levels (28-71%). These results indicate that carcinoid tumors frequently express all five sstr subtypes. The thyroid tumors also expressed multiple sstr but could lack expression of sstr2. Nevertheless, these tumors were visualized by octreotide scintigraphy, indicating that sstr2 expression is not a prerequisite for tumor imaging.
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| 26. |
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| 27. |
- Ahlman, Håkan, 1947, et al.
(författare)
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The relevance of somatostatin receptors in thyroid neoplasia.
- 1997
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Ingår i: The Yale journal of biology and medicine. - 0044-0086. ; 70:5-6, s. 523-33
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- 111In-octreotide scintigraphy in patients with persistent medullary thyroid carcinoma (MTC) visualized tumors in about half of the surgically explored sites. Tumor visualization correlated with rapid tumor growth and large tumor volume as judged from calcitonin levels. The 111In concentration ratio between tumor (T) and blood (B) in surgically excised lymph node metastases of MTC showed a large variation, with low values for microscopic and high values for macroscopic metastases in individual patients. Three cases of MTC, Hürthle cell adenoma and papillary thyroid cancer are reported with preoperative scintigraphy, T/B ratios and Northern analyses of the surgical biopsies. Visualization of tumors was possible in the absence of sstr2 (the high affinity receptor for octreotide) with the exception of microscopic tumor growth. T/B values in the patient with Hürthle cell adenoma were similar to those found in the contralateral thyroid lobe with goitre. The relatively high uptake of 111In in benign thyroid conditions probably limits the use of octreotide scintigraphy in the diagnosis of primary tumors. The technique has certain advantages over radioiodine scintigraphy after the surgical treatment of thyroid tumors: no need for withdrawal of thyroxin substitution; a possibility to diagnose metastases of tumors that do not concentrate radioiodine (MTC, Hürthle cell cancer); and complementary information about metastatic sites of non-medullary thyroid cancer (papillary and follicular tumors).
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| 28. |
- Benjegård, S A, et al.
(författare)
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Evaluation of three gamma detectors for intraoperative detection of tumors using 111In-labeled radiopharmaceuticals.
- 1999
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Ingår i: Journal of nuclear medicine : official publication, Society of Nuclear Medicine. - 0161-5505. ; 40:12, s. 2094-101
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Tidskriftsartikel (refereegranskat)abstract
- Attempts to detect tumors with intraoperative scintillation using tumor-binding radiopharmaceuticals have intensified recently. In some cases previously unknown lesions were found, but in most cases no additional lesions were detected. In this study the physical characteristics of three detector systems and their ability to detect tumors through accumulation of an 111In-labeled radiopharmaceutical were investigated. The first was a sodium iodide (NaI[TI]) detector; the second, a cesium iodide (CsI[TI]) detector; and the third, a cadmium telluride (CdTe) detector.
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| 29. |
- Fjälling, M, et al.
(författare)
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Systemic radionuclide therapy using indium-111-DTPA-D-Phe1-octreotide in midgut carcinoid syndrome.
- 1996
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Ingår i: Journal of nuclear medicine : official publication, Society of Nuclear Medicine. - 0161-5505. ; 37:9, s. 1519-21
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Tidskriftsartikel (refereegranskat)abstract
- A 55-yr-old woman with a midgut carcinoid syndrome due to metastatic spread of an ileal tumor to the liver, paraortic and mediastinal lymph nodes and to the skeleton was given systemic radionuclide therapy with 111In-DTPA-D-Phe1-octreotide. Before therapy, dosimetric calculations were performed on whole-body scintigraphs and 111In retention was shown to be long-lasting. Excretion was mainly seen during the first 24 hr after injection; thereafter whole-body retention remained stationary at 30%. Indium-111 activity in tumor biopsies and blood was measured using a gamma counter. Very high tumor-to-blood ratios were obtained: 150 for the primary tumor and 400-650 for liver metastases, which further justified radiation therapy. Indium-111-DTPA-D-Phe1-octreotide treatment was given on three separate occasions (3.0, 3.5 and 3.1 GBq) 8 and 4 wk apart. After each therapy, the patient experienced facial flush and pain over the skeletal lesions followed by symptomatic relief, even though no objective tumor regression was found radiologically after 5 mo. After initiation of octreotide treatment, there was a 14% reduction of the main tumor marker, urinary 5-HIAA. After three subsequent radionuclide therapies, there was a further 31% reduction of 5-HIAA levels. No adverse reactions, other than a slight decrease in leukocyte counts, were seen. The mean absorbed radiation dose after the three treatments was estimated to be about 10-12 Gy in liver metastases and 3-6 Gy in other tumors, depending on the size and location of the metastases. Assuming internalization of 111In into tumor cells and a radiobiological effect from short range Auger and conversion electrons, there might be a therapeutic effect on the tumor.
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| 30. |
- Wängberg, Bo, 1953, et al.
(författare)
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Survival of patients with disseminated midgut carcinoid tumors after aggressive tumor reduction.
- 1996
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Ingår i: World journal of surgery. - 0364-2313. ; 20:7
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Tidskriftsartikel (refereegranskat)abstract
- Sixty-four consecutive patients with disseminated midgut carcinoids were treated during an 8-year period according to a single clinical protocol aimed at aggressive tumor reduction by surgery alone or with subsequent hepatic artery embolization. All patients had markedly elevated urinary 5-hydroxyindoleacetic acid (5-HIAA) levels (581 +/- 79 micromol/24 h) and hormonal symptoms. Fourteen patients (22%) reached anatomic and biochemical cure by surgery alone. At follow-up, the mean 5-HIAA levels were still normal after 69.0 +/- 6. 2 months; two patients had died from unrelated causes. With the introduction of somatostatin receptor scintigraphy, subclinical disease was diagnosed in 7 of these 14 patients. Forty patients with bilobar hepatic disease underwent embolization in combination with octreotide. In this group, 5-HIAA levels were still reduced by 55% after 71 +/- 11 months of follow-up, and the 5-year survival was 56%, estimated from the total death hazard function. After embolization, two subgroups could be identified with marked differences in their long-term response to treatment. Ten patients were not embolized owing to complicating diseases. The 5-year survival for the entire series was 58%. A significantly increased risk of cardiovascular deaths was seen, which underlines the importance of total survival analysis in a disease with multiple hormonal effects. It is concluded that an active surgical approach must be recommended to patients with the midgut carcinoid syndrome. In patients with bilobar hepatic disease, embolization combined with octreotide treatment markedly reduced the 5-HIAA excretion and suggested a prolonged 5-year survival.
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