| 1. |
- Senkowski, Wojciech
(författare)
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High-throughput screening using multicellular tumor spheroids to reveal and exploit tumor-specific vulnerabilities
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- High-throughput drug screening (HTS) in live cells is often a vital part of the preclinical anticancer drug discovery process. So far, two-dimensional (2D) monolayer cell cultures have been the most prevalent model in HTS endeavors. However, 2D cell cultures often fail to recapitulate the complex microenvironments of in vivo tumors. Monolayer cultures are highly proliferative and generally do not contain quiescent cells, thought to be one of the main reasons for the anticancer therapy failure in clinic. Thus, there is a need for in vitro cellular models that would increase predictive value of preclinical research results. The utilization of more complex three-dimensional (3D) cell cultures, such as multicellular tumor spheroids (MCTS), which contain both proliferating and quiescent cells, has therefore been proposed. However, difficult handling and high costs still pose significant hurdles for application of MCTS for HTS.In this work, we aimed to develop novel assays to apply MCTS for HTS and drug evaluation. We also set out to identify cellular processes that could be targeted to selectively eradicate quiescent cancer cells. In Paper I, we developed a novel MCTS-based HTS assay and found that nutrient-deprived and hypoxic cancer cells are selectively vulnerable to treatment with inhibitors of mitochondrial oxidative phosphorylation (OXPHOS). We also identified nitazoxanide, an FDA-approved anthelmintic agent, to act as an OXPHOS inhibitor and to potentiate the effects of standard chemotherapy in vivo. Subsequently, in Paper II we applied the high-throughput gene-expression profiling method for MCTS-based drug screening. This led to discovery that quiescent cells up-regulate the mevalonate pathway upon OXPHOS inhibition and that the combination of OXPHOS inhibitors and mevalonate pathway inhibitors (statins) results in synergistic toxicity in this cell population. In Paper III, we developed a novel spheroid-based drug combination-screening platform and identified a set of molecules that synergize with nitazoxanide to eradicate quiescent cancer cells. Finally, in Paper IV, we applied our MCTS-based methods to evaluate the effects of phosphodiesterase (PDE) inhibitors in PDE3A-expressing cell lines.In summary, this work illustrates how MCTS-based HTS yields potential to reveal and exploit previously unrecognized tumor-specific vulnerabilities. It also underscores the importance of cell culture conditions in preclinical drug discovery endeavors.
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| 2. |
- Nyandoro, Stephen S., 1975, et al.
(författare)
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N-Cinnamoyltetraketide Derivatives from the Leaves of Toussaintia orientalis
- 2015
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Ingår i: Journal of natural products. - : American Chemical Society (ACS). - 0163-3864 .- 1520-6025. ; 78:8, s. 2045-2050
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Tidskriftsartikel (refereegranskat)abstract
- Seven N-cinnamoyltetraketides (1–7), including the new Z-toussaintine E (2), toussaintine F (6), and toussaintine G (7), were isolated from the methanol extract of the leaves of Toussaintia orientalis using column chromatography and HPLC. The configurations of E-toussaintine E (1) and toussaintines A (3) and D (5) are revised based on single-crystal X-ray diffraction data from racemic crystals. Both the crude methanol extract and the isolated constituents exhibit antimycobacterial activities (MIC 83.3–107.7 μM) against the H37Rv strain of Mycobacterium tuberculosis. Compounds 1, 3, 4, and 5 are cytotoxic (ED50 15.3–105.7 μM) against the MDA-MB-231 triple negative aggressive breast cancer cell line.
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| 3. |
- Villén, Johanna, et al.
(författare)
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Estimating environmental exposure to analgesic drugs : A cross-sectional study of drug utilization patterns in the area surrounding Sweden's largest drinking water source
- 2023
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Ingår i: Environmental Advances. - : Elsevier. - 2666-7657. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Use of pharmaceuticals is continuously increasing globally and their residues are recognized as a risk for theenvironment. The aim of this study was to investigate drug utilization patterns of analgesics in relation toenvironmental hazard in the region surrounding Sweden’s largest drinking water source, Lake Mälaren. This wasexamined using sales data on pharmaceuticals from the Swedish E-health Agency. The total sales of analgesics(non-steroidal anti-inflammatory drugs, paracetamol, other non-opioid analgesics, and opioids) for both humanand veterinary use in the region were analyzed for the years 2016 to 2020, in relation to the inherent environmental hazard for each active pharmaceutical ingredient (API). We found that a total of 454 tons of analgesicswere sold in the region during these 5 years. Classifications of environmental hazard were available for 16 out ofthe 45 studied APIs, accounting for 98.8% of the total mass in kilograms. Paracetamol, ibuprofen, and acetylsalicylic acid, which are all classified as low-hazard compounds, were the most commonly sold APIs. Diclofenac, the only pharmaceutical classified as high-hazard, was the fifth most commonly sold API, with a total soldmass of 2321 kg. The majority of the total sold mass of analgesics originated from dispensed prescriptions forhuman use in urban areas. Visualization of drug sales for humans and animals in different settings can be used toidentify the environmental burden of pharmaceuticals. Based on our study, we suggest that additional measuresto reduce the impacts of pharmaceuticals on the environment should primarily be directed to prescribing physicians in urban areas and campaigns targeted at the high over-the-counter sales of diclofenac. Moreover, it isimportant to address the fact that many pharmaceuticals currently have limited data on environmental hazard.
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| 4. |
- Deyou, Tsegaye, et al.
(författare)
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Isoflavones and Rotenoids from the Leaves of Millettia oblata ssp teitensis
- 2017
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Ingår i: Journal of Natural Products. - : American Chemical Society (ACS). - 0163-3864 .- 1520-6025. ; 80:7, s. 2060-2066
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Tidskriftsartikel (refereegranskat)abstract
- A new isoflavone, 8-prenylmilldrone (1), and four new rotenoids, oblarotenoids A-D (2-5), along with nine known compounds (6-14), were isolated from the CH2Cl2/CH3OH (1:1) extract of the leaves of Millettia oblata ssp. teitensis by chromatographic separation. The purified compounds were identified by NMR spectroscopic and mass spectrometric analyses, whereas the absolute configurations of the rotenoids were established on the basis of chiroptical data and in some cases by single-crystal X-ray crystallography. Maximaisoflavone J (11) and oblarotenoid C (4) showed weak activity against the human breast cancer cell line MDA-MB-231 with IC50 values of 33.3 and 93.8 mu M, respectively.
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| 5. |
- Rekić, Dinko, 1984, et al.
(författare)
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External Validation of the Bilirubin-Atazanavir Nomogram for Assessment of Atazanavir Plasma Exposure in HIV-1-Infected Patients.
- 2013
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Ingår i: The AAPS journal. - : Springer Science and Business Media LLC. - 1550-7416. ; 15:2, s. 308-15
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Tidskriftsartikel (refereegranskat)abstract
- Atazanavir increases plasma bilirubin levels in a concentration-dependent manner. Due to less costly and readily available assays, bilirubin has been proposed as a marker of atazanavir exposure. In this work, a previously developed nomogram for detection of suboptimal atazanavir exposure is validated against external patient populations. The bilirubin nomogram was validated against 311 matching bilirubin and atazanavir samples from 166 HIV-1-infected Norwegian, French, and Italian patients on a ritonavir-boosted regimen. In addition, the nomogram was evaluated in 56 Italian patients on an unboosted regimen. The predictive properties of the nomogram were validated against observed atazanavir plasma concentrations. The use of the nomogram to detect non-adherence was also investigated by simulation. The bilirubin nomogram predicted suboptimal exposure in the patient populations on a ritonavir-boosted regimen with a negative predictive value of 97% (95% CI 95-100). The bilirubin nomogram and monitoring of atazanavir concentrations had similar predictive properties for detecting non-adherence based on simulations. Although both methods performed adequately during a period of non-adherence, they had lower predictive power to detect past non-adherence episodes. Using the bilirubin nomogram for detection of suboptimal atazanavir exposure in patients on a ritonavir-boosted regimen is a rapid and cost-effective alternative to routine measurements of the actual atazanavir exposure in plasma. Its application may be useful in clinical settings if atazanavir concentrations are not available.
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| 6. |
- Xu, Bo, 1980-
(författare)
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Evolutionary and Pharmacological Studies of NPY and QRFP Receptors
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The neuropeptide Y (NPY) system consists of 3-4 peptides and 4-7 receptors in vertebrates. It has powerful effects on appetite regulation and is involved in many other biological processes including blood pressure regulation, bone formation and anxiety. This thesis describes studies of the evolution of the NPY system by comparison of several vertebrate species and structural studies of the human Y2 receptor, which reduces appetite, to identify amino acid residues involved in peptide-receptor interactions.The NPY system was studied in zebrafish (Danio rerio), western clawed frog (Xenopus tropicalis), and sea lamprey (Petromyzon marinus). The receptors were cloned and functionally expressed and their pharmacological profiles were determined using the native peptides in either binding studies or a signal transduction assay. Some peptide-receptor preferences were observed, indicating functional specialization.A receptor family closely related to the NPY receptors, called the QRFP receptors, was investigated. A QRFP receptor was cloned from amphioxus, Branchistoma floridae, showing that the receptor arose before the origin of the vertebrates. Evolutionary studies demonstrated that the ancestral vertebrate had as many as four QRFP receptors, only one of which remains in mammals today. This correlates with the NPY receptor family, located in the same chromosomal regions, which had seven members in the ancestral vertebrate but only 4-5 in living mammals. Some vertebrates have considerably more complex NPY and QRFP receptor systems than humans and other mammals.Two studies investigated interactions of NPY-family peptides with the human Y2 receptor. Candidate residues, selected based on structural modeling and docking, were mutated to disrupt possible interactions with peptide ligands. The modified receptors were expressed in cultured cells and investigated by measuring binding and functional responses. Several receptor residues were found to influence peptide-receptor interactions, some of which are involved in maintaining receptor structure. In a pilot study, the kinetics of peptide-receptor interaction were found to be very slow, of the order several hours.In conclusion, this thesis clarifies evolutionary relationships for the complex NPY and QRFP peptide-receptor systems and improves the structural models of the human NPY-family receptors, especially Y2. These results will hopefully facilitate drug design for targeting of NPY-family receptors.
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| 7. |
- Ragno, Rino, et al.
(författare)
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Structure-based modeling and target-selectivity prediction
- 2014
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Patent (populärvet., debatt m.m.)abstract
- The present invention provides, inter alia, methods, models, and systems for selecting an effector having specificity for a target molecule. The methods and systems of the present invention involve several steps, including compiling a database containing structural data for a library of molecules and a population of ligands and activity data, establishing structure-based equivalence of sequence elements in the library of molecules, determining likely spatial orientations of population ligands in library molecules, calculating interaction energies for each ligand-molecule pair, generating statistical models that are predictive of sequence elements likely to contribute to a differential effect of ligands on molecules, selecting an effector that is likely to have a desired specificity for the target molecule, experimentally determining activity data for effector-library molecule pairs, and at least once repeating the steps listed above wherein the effector is a member of the population of ligands.
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| 8. |
- Magnusson, Marie, et al.
(författare)
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A placebo-controlled study of retinal blood flow changes by pentoxifylline and metabolites in humans
- 2006
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Ingår i: British Journal of Clinical Pharmacology. - : Wiley. - 0306-5251 .- 1365-2125. ; 61:2, s. 138-147
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Tidskriftsartikel (refereegranskat)abstract
- AIM: To investigate the possible effects of pentoxifylline metabolites on retinal blood flow in humans. METHODS: A randomized, placebo-controlled, four-period cross-over study that was observer blinded and partly blinded for the eight participants. On one occasion a placebo was given as an intravenous (i.v.) infusion over 100 min. On the other three occasions pentoxifylline was administered as i.v. infusions over 100 min at a rate of 3 mg min(-1). Before two of the pentoxifylline infusions the subjects were pretreated with either ciprofloxacin or rifampicin. Retinal blood flow was measured by scanning laser doppler flowmetry (SLDF) in a selected area of the central temporal retina before, during and until 5 h after the end of infusion. Blood samples for concentration analyses of pentoxifyllin, R-M1, S-M1, M4 and M5 were taken serially and areas under the curves (AUCs) were calculated. Linear mixed models were used for the statistical analyses. RESULTS: Mean AUCs (ng h ml(-1)) were significantly increased for pentoxifylline (1964 vs. 1453) and S-M1 (5804 vs. 4227), but not R-M1 when pentoxifylline was co-administered with ciprofloxacin. The mean AUC for M5 was significantly reduced when subjects were pretreated with rifampicin (2041 vs. 3080). Pentoxifylline with and without pretreatment with rifampicin significantly increased retinal blood flow assessed as mean flow, pulsation (i.e. 1-systole/diastole), and diastolic flow (but not during systole), compared with placebo. The increases over placebo were more pronounced on diastolic flow, 9.7% (95% confidence interval 4.2, 15.5) than on mean flow, 4.6% (1.1, 8.3) after pentoxifylline administration. With pentoxifylline after rifampicin pretreatment the corresponding differences were 11.7% (5.8, 17.9) and 5.1% (1.4, 7.8) over placebo, respectively. After co-administration of pentoxifylline and ciprofloxacin we saw only a nonsignificant trend towards increased flow during diastole, but a significant decrease in pulsation. When AUCs for pentoxifylline and its metabolites were used as regressor variables to retinal mean flow we found that pentoxifylline, R-M1 and M5 had coefficients with a positive sign indicating that they enhanced the retinal blood flow. In contrast, S-M1 and M4 had coefficients with negative sign and thus appeared to decrease the blood flow in subjects treated with pentoxifylline. CONCLUSION: The R-M1 and M5 metabolites of pentoxifylline contributed significantly to the effects of pentoxifylline on retinal blood flow.
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| 9. |
- Ludvigsson, Jonas F., et al.
(författare)
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Coeliac disease and the risk of fractures : a general population-based cohort study
- 2007
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Ingår i: Alimentary Pharmacology and Therapeutics. - Oxford : Blackwell Scientific. - 0269-2813 .- 1365-2036. ; 25:3, s. 273-285
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background: Earlier studies have suggested that untreated coeliac disease may be associated with osteoporosis, but results are contradictory for the risk of long-term fractures.Aim: To study the association between coeliac disease and fractures.Methods: We used Cox regresson to examine the future risk of hip fracture and fracture of any type in more than 13 000 individuals with coeliac disease and 65 000 age- and sex-matched reference individuals in a general population-based cohort.Results: During follow-up, 1365 first hip fractures and 4847 fractures of any type occurred. Coeliac disease was positively associated with subsequent hip fracture (hazard ratio = 2.1; 95% CI = 1.8-2.4) (in children: hazard ratio = 2.6; 95% CI = 1.1-6.2) and fractures of any type (hazard ratio = 1.4; 95% CI = 1.3-1.5) (in children: hazard ratio = 1.1; 95% CI = 1.0-1.2). The absolute excess risk of hip fractures in children with coeliac disease was 4/100 000 person-years. Incidence ratios for hip fracture in individuals with CD were around two both prior to diagnosis of coeliac disease and afterwards; this risk increase remained 20 years after diagnosis of coeliac disease.Conclusions: Individuals with coeliac disease, including children with coeliac disease, may be at increased risk of hip fracture and fracture of any type. Coeliac disease may be positively associated with long-term hip fracture risk.
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| 10. |
- Nilsson, C. L., et al.
(författare)
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Chromosome 19 Annotations with Disease Speciation: A First Report from the Global Research Consortium
- 2013
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Ingår i: Journal of Proteome Research. - : American Chemical Society (ACS). - 1535-3893 .- 1535-3907. ; 12:1, s. 134-149
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Tidskriftsartikel (refereegranskat)abstract
- A first research development progress report of the Chromosome 19 Consortium with members from Sweden, Norway, Spain, United States, China and India, a part of the Chromosome-centric Human Proteome Project (C-HPP) global initiative, is presented (http://www.c-hpp.org). From the chromosome 19 peptide-targeted library constituting 6159 peptides, a pilot study was conducted using a subset with 125 isotope-labeled peptides. We applied an annotation strategy with triple quadrupole, ESI-Qtrap, and MALDI mass spectrometry platforms, comparing the quality of data within and in between these instrumental set-ups. LC–MS conditions were outlined by multiplex assay developments, followed by MRM assay developments. SRM was applied to biobank samples, quantifying kallikrein 3 (prostate specific antigen) in plasma from prostate cancer patients. The antibody production has been initiated for more than 1200 genes from the entire chromosome 19, and the progress developments are presented. We developed a dedicated transcript microarray to serve as the mRNA identifier by screening cancer cell lines. NAPPA protein arrays were built to align with the transcript data with the Chromosome 19 NAPPA chip, dedicated to 90 proteins, as the first development delivery. We have introduced an IT-infrastructure utilizing a LIMS system that serves as the key interface for the research teams to share and explore data generated within the project. The cross-site data repository will form the basis for sample processing, including biological samples as well as patient samples from national Biobanks.
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