| 11. |
- Seldén, Tor, et al.
(författare)
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LC-MS-MS analysis of buprenorphine and norbuprenorphine in whole blood from suspected drug users
- 2011
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Ingår i: Forensic Science International. - : Elsevier. - 0379-0738 .- 1872-6283. ; 209:1-3, s. 113-119
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Tidskriftsartikel (refereegranskat)abstract
- A liquid chromatography tandem mass spectrometry method is described for the analysis of buprenorphine and norbuprenorphine in whole blood. Linearity was achieved between 0.2-5 ng/g for buprenorphine and 0.5-5 ng/g for norbuprenorphine. Stability studies on spiked whole blood and an authentic sample showed no degradation of buprenorphine- and norbuprenorphine-glucuronide to their respective aglycones. Buprenorphine and norbuprenorphine showed some degradation when stored at 4 degrees C for three weeks, but was stable when stored at -20 degrees C for 4 weeks. The method was applied to forensic cases of driving under the influence of drugs (DUID) and petty drug offences (PDO) during 2007-2009. Out of 2459 cases analyzed, 322 were positive for both buprenorphine and norbuprenorphine (13%), 219 for buprenorphine only (9%), and 12 for norbuprenorphine only (0.5%). The mean and median concentrations (N = 322) were 1.7 and 1.0 ng/g, respectively, for buprenorphine and norbuprenorphine. The mean and median norbuprenorphine/buprenorphine ratios were 1.5 and 1.1, respectively. There was no significant difference in concentration ratios for DUID and PDO cases (p andgt; 0.05). We conclude that the described method for analysis of buprenorphine and norbuprenorphine in whole blood could be used to investigate use or misuse of buprenorphine but that many of the cases presented with very low concentrations of buprenorphine. We also conclude that analysis should be performed within two weeks unless samples are stored frozen prior to analysis.
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| 12. |
- Seldén, Tor, et al.
(författare)
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Toxicological and pathological findings in a series of buprenorphine related deaths. Possible risk factors for fatal outcome
- 2012
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Ingår i: Forensic Science International. - : Elsevier. - 0379-0738 .- 1872-6283. ; 220:1-3, s. 284-290
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Tidskriftsartikel (refereegranskat)abstract
- Buprenorphine is considered to have little respiratory side effects at therapeutic doses and the partial agonistic properties should produce a "ceiling effect for respiratory depression at higher doses. Still, there are several reports on buprenorphine related deaths. Most deaths involve drug users and the co-administration of other CNS depressant drugs as well as reduced tolerance have been suggested to be risk factors. The primary aims were to investigate if lack of tolerance and/or co-ingestion of other psychotropic drugs are significant risk factors in buprenorphine fatalities. From July 2005 to September 2009, all autopsy cases where buprenorphine or norbuprenorphine had been detected in femoral blood and where analysis of buprenorphine had been performed in urine were selected. Results from the postmortem examination and toxicology were compiled. Postmortem toxicology was performed using the routine methodology at the laboratory. In total, 97 subjects were included in the study. These were divided into four groups; Intoxication with buprenorphine (N = 41), Possible intoxication with buprenorphine (N = 24), Control cases where buprenorphine was not the cause of death (N = 14), and Unclear (N = 18). The metabolite to parent compound ratios in both blood and urine in the Intoxication group were significantly different from those in the Control and Unclear groups. An extensive poly-drug use was seen in all groups with several additional opioids in the Possible group (54%) and in the Unclear group (78%) and hypnotics or sedatives in more than 75% of the Intoxication, Possible, and Unclear cases. Illicit drugs were present in all groups but not to a great extent with amphetamine and tetrahydrocannabinol as the main findings. Interestingly, 4 cases in the Intoxication group presented with no other significant drugs in blood other than buprenorphine. We conclude that a lethal concentration of buprenorphine in blood cannot be defined. Instead the analysis of blood as well as urine can be an important tool to show that the drug was taken shortly before death and to rule out a continuous use of buprenorphine supporting the notion that abstinence is an important risk factor. The presence of alprazolam in more than 40% of the Intoxications and the presence of hypnotics and sedatives in 75% of the Intoxications suggests that these drugs interact with buprenorphine producing toxic effects that buprenorphine alone would not have produced. Still, in 10% of the Intoxications no other drugs were found indicating that under certain circumstances buprenorphine alone may produce respiratory depression resulting in death.
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| 13. |
- Spaulding, Kirsty, et al.
(författare)
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Dynamics of Hippocampal Neurogenesis in Adult Humans
- 2013
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Ingår i: Cell. - Maryland Heights, MO, USA : Elsevier. - 0092-8674 .- 1097-4172. ; 153:6, s. 1219-1227
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Tidskriftsartikel (refereegranskat)abstract
- Adult-born hippocampal neurons are important for cognitive plasticity in rodents. There is evidence for hippocampal neurogenesis in adult humans, although whether its extent is sufficient to have func- tional significance has been questioned. We have assessed the generation of hippocampal cells in humans by measuring the concentration of nuclear- bomb-test-derived 14C in genomic DNA, and we present an integrated model of the cell turnover dy- namics. We found that a large subpopulation of hip- pocampal neurons constituting one-third of the neu- rons is subject to exchange. In adult humans, 700 new neurons are added in each hippocampus per day, corresponding to an annual turnover of 1.75% of the neurons within the renewing fraction, with a modest decline during aging. We conclude that neu- rons are generated throughout adulthood and that the rates are comparable in middle-aged humans and mice, suggesting that adult hippocampal neuro- genesis may contribute to human brain function.
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| 14. |
- Taqi, Malik Mumtaz, et al.
(författare)
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Prodynorphin CpG-SNPs associated with alcohol dependence : elevated methylation in the brain of human alcoholics
- 2011
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Ingår i: Addiction Biology. - : Wiley. - 1355-6215 .- 1369-1600. ; 16:3, s. 499-509
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Tidskriftsartikel (refereegranskat)abstract
- The genetic, epigenetic and environmental factors may influence the risk for neuropsychiatric disease through their effects on gene transcription. Mechanistically, these effects may be integrated through regulation of methylation of CpG dinucleotides overlapping with single-nucleotide polymorphisms (SNPs) associated with a disorder. We addressed this hypothesis by analyzing methylation of prodynorphin (PDYN) CpG-SNPs associated with alcohol dependence, in human alcoholics. Postmortem specimens of the dorsolateral prefrontal cortex (dl-PFC) involved in cognitive control of addictive behavior were obtained from 14 alcohol-dependent and 14 control subjects. Methylation was measured by pyrosequencing after bisulfite treatment of DNA. DNA binding proteins were analyzed by electromobility shift assay. Three PDYN CpG-SNPs associated with alcoholism were found to be differently methylated in the human brain. In the dl-PFC of alcoholics, methylation levels of the C, non-risk variant of 3'-untranslated region (3'-UTR) SNP (rs2235749; C > T) were increased, and positively correlated with dynorphins. A DNA-binding factor that differentially targeted the T, risk allele and methylated and unmethylated C allele of this SNP was identified in the brain. The findings suggest a causal link between alcoholism-associated PDYN 3'-UTR CpG-SNP methylation, activation of PDYN transcription and vulnerability of individuals with the C, non-risk allele(s) to develop alcohol dependence.
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| 15. |
- Tjomsland, Vegard, et al.
(författare)
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IL-1α Sustains the Inflammation in Human Pancreatic Cancer Microenvironment by Targeting Cancer Associated Fibroblasts
- 2010
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The tumor microenvironment in pancreatic ductal adenocarcinoma (PDAC) is dynamic with an extensive interaction between the stroma and tumor cells. Our aim for this study was to delineate the cross-talk between PDAC and cancer-associated fibroblasts (CAFs) with focus on the mechanism creating the chronic inflammatory tumor milieu. We assessed the effect cross talk between primary PDAC and CAF cell lines propagated from tumors had on the creation and sustenance of an inflammatory environment and what factors that were involved in establishing the inflammation. The coculture of PDAC and CAF cell lines, propagated from tumor tissues, enhanced the levels of inflammatory factors including IL-1α, IL-6, CXCL8, VEGFA, CCL20, and COX-2. The production of these factors correlated with the expression detected in vivo in PDAC tissues. The key producers of nearly all inflammatory factors were the CAFs and not the tumor cells. IL-1α was produced by the tumor cell lines, whereas almost all IL-1RI was expressed by CAFs thus corresponding to their in vivo expression profile in PDAC tissues, indicating a role for the IL-1 signaling cascade in a tumor favorable microenvironment. Neutralization of the IL-1α pathway efficiently diminished the cross talk induced production of inflammatory factors, both in stroma and tumor cells. These data suggest that the cross-talk between PDAC cells and the main stroma cell type, i.e. CAFs, is one contributing factor in the formation of the inflammatory tumor environment and we propose that the neutralization of IL-1α pathway might be a potential therapy for this cancer.
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| 16. |
- Tjomsland, Vegard, 1978-, et al.
(författare)
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Interleukin 1α sustains the expression of inflammatory factors in human pancreatic cancer microenvironment by targeting cancer-associated fibroblasts
- 2011
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Ingår i: Neoplasia. - : Neoplasia Press. - 1522-8002 .- 1476-5586. ; 13:8, s. 664-675
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Tidskriftsartikel (refereegranskat)abstract
- The tumor microenvironment in pancreatic ductal adenocarcinoma (PDAC) is dynamic with an extensive interaction between the stroma and tumor cells. The aim for this study was to delineate the cross-talk between PDAC and cancer-associated fibroblasts (CAFs) with focus on the mechanism creating the chronic inflammatory tumor milieu. We assessed the effects of the cross-talk between primary PDAC and CAF cell lines on the creation and sustenance of the inflammatory tumor microenvironment in pancreatic cancer. The coculture of primary PDAC and CAF cell lines enhanced the levels of inflammatory factors including IL-1á, IL-6, CXCL8, VEGFA, CCL20, and COX-2. CAFs were superior to tumor cells regarding the production of most inflammatory factors and tumor cell associated IL-1á was established as the initiator of the enhanced production of inflammatory factors through the binding of IL-1á to the active IL-1 receptor (IL-1R1) expressed predominantly by CAFs. Furthermore, we found a positive correlation between IL-1á and CXCL8 expression levels in PDAC tissues and correlation between IL-1á expression and the clinical outcome of the patients. This confirmed an important role for the IL-1 signaling cascade in the creation and sustenance of a tumor favorable microenvironment. Neutralization of the IL-1á signaling efficiently diminished the cross-talk induced production of inflammatory factors. These data suggest that the cross-talk between PDAC cells and the main stroma cell type, i.e. CAFs, is one essential factor in the formation of the inflammatory tumor environment and we propose that neutralization of the IL-1á signaling might be a potential therapy for this cancer.
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| 17. |
- Tjomsland, Vegard, et al.
(författare)
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Pancreatic cancer microenvironment has a high degree of inflammation and infiltrating immune cells in its stroma
- 2010
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Tumor microenvironment is composed of tumor cells, fibroblasts, and infiltrating immune cells, and other cellular components, which work together and create an inflammatory environment favoring tumor progression. The present study aimed to characterize the expression and location of immune cells and investigate inflammatory factors that influence pancreatic ductal adenocarcinoma (PDAC). Methods: qPCRs and immunohistological stainings were performed for inflammatory factors and immune cells localized in tumor tissues from patients with PDAC (N=30). Results: All PDAC tissues had significant increased levels of inflammatory and chemotactic factors such as IL-1α, COX-2, CXCL8, CCL2, and CCL20 as compared to controls. The PDAC stroma, i.e. the fibrosis surrounding the tumor, was the main producer of these factors with the exception of IL-1α, which was expressed by tumor cells and some infiltrating immune cells. The gene expression for immune cell specific markers CD163, CD1c, CD303, and CD8, corresponding to macrophages, myeloid dendritic cells (DCs), plasmacytoid DCs, and cytotoxic T lymphocytes (CTL), respectively, were all significantly increased in PDAC tissues. Immunostaining of the tumor tissue confirmed the elevated levels of infiltrating macrophages, DCs, mature DCs, and cytotoxic T lymphocytes (CTL). The different immune cells were in nearly all cases localized in the fibrotic tissue adjacent to tumor nests. Production of CXCL8 mRNA and protein by the stroma was dependent on the tumor expression of IL-1α. Of importance, we found a correlation in expression of the proinflammatory factor IL-1α and the PDAC patients’ survival time. Conclusion: PDAC cells seem to take advantage of IL-1α to create an inflammatory microenvironment with high degree of fibrosis and the ability to both recruit and activate immune cells and the level of inflammation in this environment influenced the clinical outcome for the patients. Therapies targeting the inflammation might be beneficial for the survival of patients with PDAC.
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| 18. |
- Tjomsland, Vegard, et al.
(författare)
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The Desmoplastic Stroma Plays an Essential Role in the Accumulation and Modulation of Infiltrated Immune Cells in Pancreatic Adenocarcinoma
- 2011
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Ingår i: Clinical & Developmental Immunology. - : Hindawi Publishing Corporation. - 1740-2522 .- 1740-2530. ; 2011:212810
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Tidskriftsartikel (refereegranskat)abstract
- Tumor microenvironment is composed of tumor cells, fibroblasts, and infiltrating immune cells, which all work together and create an inflammatory environment favoring tumor progression. The present study aimed to investigate the role of the desmoplastic stroma in pancreatic ductal adenocarcinoma (PDAC) regarding expression of inflammatory factors and infiltration of immune cells and their impact on the clinical outcome. The PDAC tissues examined expressed significantly increased levels of immunomodulatory and chemotactic factors (IL-6, TGF beta, IDO, COX-2, CCL2, and CCL20) and immune cell-specific markers corresponding to macrophages, myeloid, and plasmacytoid dendritic cells (DCs) as compared to controls. Furthermore, short-time survivors had the lowest levels of DC markers. Immunostainings indicated that the different immune cells and inflammatory factors are mainly localized to the desmoplastic stroma. Therapies modulating the inflammatory tumor microenvironment to promote the attraction of DCs and differentiation of monocytes into functional DCs might improve the survival of PDAC patients.
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| 19. |
- Yeung, Maggie, et al.
(författare)
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Dynamics of Oligodendrocyte Generation and Myelination in the Human Brain
- 2014
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Ingår i: Cell. - Maryland Heights : Elsevier. - 0092-8674 .- 1097-4172. ; 159:4, s. 766-774
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Tidskriftsartikel (refereegranskat)abstract
- The myelination of axons by oligodendrocytes has been suggested to be modulated by experience, which could mediate neural plasticity by optimizing the performance of the circuitry. We have assessed the dynamics of oligodendrocyte generation and myelination in the human brain. The number of oligodendrocytes in the corpus callosum is established in childhood and remains stable after that. Analysis of the integration of nuclear bomb test-derived 14C revealed that myelin is exchanged at a high rate, whereas the oligodendrocyte population in white matter is remarkably stable in humans, with an annual exchange of 1/300 oligodendrocytes. We conclude that oligodendrocyte turnover contributes minimally to myelin remodeling in human white matter and that this instead may be carried out by mature oligodendrocytes, which may facilitate rapid neural plasticity.
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