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)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. |
- Ludvigsson, Jonas F., et al.
(författare)
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A population-based study of coeliac disease, neurodegenerative and neuroinflammatory diseases
- 2007
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Ingår i: Alimentary Pharmacology and Therapeutics. - : Wiley. - 0269-2813 .- 1365-2036. ; 25:11, s. 1317-1327
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundIt has been suggested that coeliac disease (CD) is associated with several neurological diseases. However, the evidence of such an association is inconclusive as earlier research has often been based on small numbers with retrospective data collection.AimTo use Cox regression to examine the risk of neurological disease in individuals with CD.MethodsThrough Swedish national registers we identified some 14 000 individuals with a diagnosis of CD (1964–2003) and 70 000 reference individuals matched for age, sex, calendar year and county.ResultsCoeliac disease was associated with later polyneuropathy [hazard ratio (HR) = 3.4; 95% CI = 2.3–5.1]. We found no statistically significant association between CD and subsequent multiple sclerosis (HR = 0.9; 95% CI = 0.3–2.3), Parkinson’s disease (HR = 1.2; 95% CI = 0.8–1.9), Alzheimer’s disease (HR = 1.5; 95% CI = 0.9–2.6), hereditary ataxia (HR = 1.3; 95% CI = 0.5–3.6), the symptom ataxia (HR = 1.9; 95% CI = 0.6–6.2), Huntington’s disease (HR = 1.7; 95% CI = 0.3–8.6), myasthenia gravis (HR = 0.8; 95% CI = 0.2–3.8) or spinal muscular atrophy (HR = 0.5; 95% CI = 0.1–3.8). Prior polyneuropathy was associated with subsequent CD (odds ratio = 5.4; 95% CI = 3.6–8.2).ConclusionsThe association between CD and polyneuropathy indicates shared risks. We suggest that individuals with polyneuropathy routinely undergo screening for CD. There is no notable association between CD and other neurological outcomes investigated in this study.
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3. |
- 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)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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4. |
- 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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5. |
- Ekman, Elisabet, et al.
(författare)
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Awareness among nurses about reporting of adverse drug reactions in Sweden
- 2012
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Ingår i: Drug, Healthcare and Patient Safety. - : Dove Medical Press Ltd.. - 1179-1365 .- 1179-1365. ; 4, s. 61-66
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Tidskriftsartikel (refereegranskat)abstract
- Background: The purpose of this study was to investigate awareness among nurses regarding their new role as reporters of adverse drug reactions in Sweden and factors that may influence reporting by nurses.Methods: In 2007, all nurses were included in the adverse drug reaction reporting scheme in Sweden. A questionnaire was sent to 753 randomly selected nurses in September 2010.Results: Of the 453 (60%) responding nurses, 265 (58%) were aware that nurses were included in the reporting of adverse drug reactions. Sixty-one nurses (14%) stated that they had reported an adverse drug reaction. Fifteen percent (n = 70) of the respondents had received training about reporting of adverse drug reactions. Almost one third of these (n = 21, 30%) had reported an adverse drug reaction on at least one occasion. Among nurses without training, a smaller proportion (n = 40, 11%, P < 0.05) had reported an adverse drug reaction on at least one occasion. The two factors considered most important by nurses for reporting were the severity of the adverse drug reaction and if the reaction was to a newly approved drug. A majority of the nurses (n = 397, 88%) were interested in a training course in pharmacology as part of their ongoing professional development. One third (32%) of all nurses stated that one reason for not reporting a suspected adverse drug reaction was that the physician responsible did not regard the reaction necessary to report.Conclusion: We found that more than half of the study population of nurses in Sweden were aware of their new role as reporters of adverse drug reactions, but few of the responding nurses had reported an adverse drug reaction. Given that training seems to be associated with high reporting frequency, we suggest more training in pharmacovigilance for nurses.
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6. |
- Klaminder, Jonatan, 1976-, et al.
(författare)
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Less anxious salmon smolt become easy prey during downstream migration
- 2019
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Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 687, s. 488-493
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Tidskriftsartikel (refereegranskat)abstract
- Hatchery-reared salmon smolt used for supplementary stocking often display poor migration behavior compared to wild smolt, which reduces the success of this management action. Oxazepam, an anxiolytic drug, has been shown to intensify salmon smolt migration in mesocosm experiments, and treatment with this drug has, therefore, been suggested as a management option to improve downstream smolt migration. In this study, we tested this by assessing migration performance of hatchery-reared Atlantic salmon (Salmo salar) smolt along a 21-km long natural river-to-sea migration route in a boreal river in Northern Sweden. Using acoustic telemetry, the migration rate and survival of smolt that had been exposed to oxazepam (200 mu g L-1, N = 20) was monitored and compared with a control group (N = 20) of unexposed smolt. Exposed smolt took significantly longer time to initiate migration after release compared to the control fish, but after that we observed no significant difference in downstream migration speed. However, exposed smolt had considerably higher probability of being predated on compared to control smolt. We attribute these results to increased risk-taking and higher activity in oxazepam-exposed smolt, which in turn increased initial non-directional exploratory behavior and decreased predator vigilance. These results are discussed based on current concerns for ecological implications of behavioral modifications induced by pharmaceutical pollution and climate change. We conclude that exposure to oxazepam is an unsuitable management option to prime migration of reared salmon in natural systems.
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7. |
- Tjäderborn, Micaela, 1983-
(författare)
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Psychoactive prescription drug use disorders, misuse and abuse : Pharmacoepidemiological aspects
- 2016
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Doktorsavhandling (övrigt vetenskapligt)abstract
- Background: There is a widespread and increasing use of psychoactive prescription drugs, such as opioid analgesics, anxiolytics, hypnotics and anti-epileptics, but their use is associated with a risk of drug use disorder, misuse and abuse. Today, these are globally recognized and emerging public health concerns.Aim: The aim of this thesis is to estimate the prevalence of psychoactive prescription drug (PPD) use disorders, misuse and abuse, and to investigate the association with some potential risk factors.Methods: A study using register data from forensic cause of death investigations investigated and described cases of fatal unintentional intoxication with tramadol (Study I). Based on register data on spontaneously reported adverse drug reactions (ADRs) reported cases of tramadol dependence were investigated and summarised (Study II). In a study in suspected drug-impaired drivers with a toxicology analysis confirming the intake of one out of five pre-specified PPDs, the prevalence of non-prescribed use was assessed and associated factors were investigated (Study III). From a cohort of patients initiating prescribed treatment with pregabalin, using data on prescription fills, a study investigated longitudinal utilisation patterns during five years with regards to use of the drug above the maximum approved daily dose (MAD), and factors associated with the utilisation patterns (Study IV).Results: In the first study, 17 cases of unintentional intoxications were identified, of which more concerned men, the median age was 44 years and the majority used multiple psychoactive substances (alcohol, illicit drugs and prescription drugs). The second study identified 104 spontaneously reported cases of tramadol dependence, in which more concerned women, the median age was 45 years, and a third reported a history of substance abuse and 40% of past psychoactive medication use. In the third study, more than half of the individuals suspected of drug-impaired driving used the drug without a recent prescription. Non prescribed use was most frequent in users of benzodiazepines and tramadol, and was more likely in younger individuals and in multiple-substance users. In the last paper five longitudinal utilisation patterns were found in pregabalin users, with two patterns associated with a particularly high risk of doses above the maximum approved dosing recommendation. This pattern of use was associated with male sex, younger age, non-urban residency and a recent prescribed treatment with an antiepileptic or opioid analgesic drug.Conclusions: This thesis shows that psychoactive prescription drug use disorders, misuse and abuse occur and may have serious and even fatal consequences. The prevalence varies between different drugs and populations. Abuse and misuse seem to be more common in young people. Fatal intoxications and misuse of prescribed drugs may be more common in men, while drug use disorders following prescribed treatment may be more common in women and non-prescribed use equally distributed between women and men. Individuals with a history of mental illness, substance use disorder or abuse, or of past use of psychoactive medications are likely important risk groups. In summary, the findings suggest a potential for improvements in the utilisation of psychoactive prescription drugs. The results may be useful in the planning of clinical and regulatory preventive interventions to promote the rational, individualised and safe use of such drugs.
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8. |
- 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)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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9. |
- Skårberg, Kurt, et al.
(författare)
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The development of multiple drug use among anabolic-androgenic steroid users : six subjective case reports
- 2008
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Ingår i: Substance Abuse Treatment, Prevention, and Policy. - London : BioMed Central. - 1747-597X. ; 3, s. 24-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The inappropriate use of anabolic androgenic steroids (AAS) was originally a problem among athletes but AAS are now often used in nonsport situations and by patients attending regular addiction clinics. The aim of this study was to improve understanding of the development of multiple drug use in patients seeking treatment at an addiction clinic for AAS-related problems. METHODS: We interviewed six patients (four men and two women) with experience of AAS use who were attending an addiction clinic for what they believed were AAS-related problems. The patients were interviewed in-depth about their life stories, with special emphasis on social background, substance use, the development of total drug use and subjective experienced psychological and physical side effects. RESULTS: There was significant variation in the development of drug use in relation to social background, onset of drug use, relationship to AAS use and experience of AAS effects. All patients had initially experienced positive effects from AAS but, over time, the negative experiences had outweighed the positive effects. All patients were dedicated to excess training and took AAS in combination with gym training, indicating that the use of these drugs is closely related to this form of training. Use of multiple drugs was common either in parallel with AAS use or serially. CONCLUSIONS: The study shows the importance of understanding how AAS use can develop either with or without the concomitant use of other drugs of abuse. The use of AAS can, however, progress to the use of other drugs. The study also indicates the importance of obtaining accurate, comprehensive information about the development of AAS use in designing treatment programmes and prevention strategies in this area.
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10. |
- Hellström, Lina, et al.
(författare)
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Impact of the Lund Integrated Medicines Management (LIMM) model on medication appropriateness and drug-related hospital revisits.
- 2011
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Ingår i: European Journal of Clinical Pharmacology. - : Springer Science and Business Media LLC. - 0031-6970 .- 1432-1041. ; 67:7, s. 741-752
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Tidskriftsartikel (refereegranskat)abstract
- PurposeTo examine the impact of systematic medication reconciliations when admitted to hospital, and medication review while in hospital, on the number of inappropriate medications and unscheduled drug-related hospital revisits in elderly patients.MethodsA prospective, controlled study in 210 patients, aged 65 years or older, who were admitted to one of three internal medicine wards at a University Hospital in Sweden. Patients received either standard care or care according to the Lund Integrated Medicines Management (LIMM) model. A multi-professional team, including a clinical pharmacist, provided medication reconciliations on admission and medication reviews during the hospital stay for the LIMM group. Blinded reviewers evaluated the appropriateness of the prescribing (using the Medication Appropriateness Index) on admission and discharge, and assessed the probability that a drug-related problem was the reason for any patient readmitted to hospital or visiting the emergency department within three months of discharge (using WHO causality criteria).ResultsThere was a greater decrease in the number of inappropriate drugs in the intervention group than in the control group for both the intention-to-treat population (51% [95% CI 43-58%] versus 39% [95% CI 30-48%], p=0.0446) and the per-protocol population (60% [95% CI 51-67%] versus 44% [95% CI 34-52 %], p=0.0106). There were 6 revisits to hospital in the intervention group which were judged as ‘possibly, probably or certainly drug-related’, compared with 12 in the control group (p=0.0469).ConclusionIn this study, medication reconciliation and reviews provided by a clinical pharmacist in a multi-professional team significantly reduced the number of inappropriate drugs and unscheduled drug-related hospital revisits for elderly patients.
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