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Jakobsen I, Sundkvist M, Björn N, Gréen H, Lotfi K. Early changes in gene expression profiles in AML patients during induction chemotherapy. BMC Genomics 2022; 23:752. [PMCID: PMC9664790 DOI: 10.1186/s12864-022-08960-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 10/20/2022] [Indexed: 11/16/2022] Open
Abstract
Abstract
Background
Elucidation of the genetic mechanisms underlying treatment response to standard induction chemotherapy in AML patients is warranted, in order to aid in risk-adapted treatment decisions as novel treatments are emerging. In this pilot study, we explored the treatment-induced expression patterns in a small cohort of AML patients by analyzing differential gene expression (DGE) over the first 2 days of induction chemotherapy.
Methods
Blood samples were collected from ten AML patients at baseline (before treatment initiation) and during the first 2 days of treatment (Day 1; approximately 24 h, and Day 2; approximately 48 h after treatment initiation, respectively) and RNA was extracted for subsequent RNA sequencing. DGE between time points were assessed by pairwise analysis using the R package edgeR version 3.18.1 in all patients as well as in relation to treatment response (complete remission, CR, vs non-complete remission, nCR). Ingenuity Pathway Analysis (Qiagen) software was used for pathway analysis and visualization.
Results
After initial data quality control, two patients were excluded from further analysis, resulting in a final cohort of eight patients with data from all three timepoints. DGE analysis demonstrated activation of pathways with genes directly or indirectly associated with NF-κB signaling. Significant activation of the NF-κB pathway was seen in 50% of the patients 2 days after treatment start, while iNOS pathway effects could be identified already after 1 day. nCR patients displayed activation of pathways associated with cell cycle progression, oncogenesis and anti-apoptotic behavior, including the STAT3 pathway and Salvage pathways of pyrimidine ribonucleotides. Notably, a significant induction of cytidine deaminase, an enzyme responsible for the deamination of Ara-C, could be observed between baseline and Day 2 in the nCR patients but not in patients achieving CR.
Conclusions
In conclusion, we show that time-course analysis of gene expression represents a feasible approach to identify relevant pathways affected by standard induction chemotherapy in AML patients. This poses as a potential method for elucidating new drug targets and biomarkers for categorizing disease aggressiveness and evaluating treatment response. However, more studies on larger cohorts are warranted to elucidate the transcriptional basis for drug response.
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Björn N, Jakobsen I, Udagawa C, Brandén E, Koyi H, Lewensohn R, De Petris L, Zembutsu H, Gréen H. The association of four genetic variants with myelosuppression in gemcitabine-treated Japanese is not evident in gemcitabine/carboplatin-treated Swedes. Basic Clin Pharmacol Toxicol 2022; 130:513-521. [PMID: 35132780 PMCID: PMC9303231 DOI: 10.1111/bcpt.13712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 01/31/2022] [Accepted: 02/01/2022] [Indexed: 11/26/2022]
Abstract
Gemcitabine/carboplatin‐induced myelosuppressive adverse drug reactions (ADRs) are clinical problems leading to patient suffering and dose alterations. There is a need for personalised medicine to improve treatment effects and patients' well‐being. We tested four genetic variants, rs11141915, rs1901440, rs12046844 and rs11719165, previously suggested as potential biomarkers for gemcitabine‐induced leukopenia/neutropenia in Japanese patients, in 213 Swedish gemcitabine/carboplatin‐treated non‐small cell lung cancer (NSCLC) patients. DNA was genotyped using TaqMan probes and real‐time PCR. The relationships between the risk alleles and low toxicity (non‐ADR: Common Terminology Criteria for Adverse Events [CTCAE] grades 0) or high toxicity (ADR: CTCAE grades 3–4) of platelets, leukocytes and neutrophils were evaluated using Fisher's exact test. The risk alleles did not correlate with myelosuppression, and the strongest borderline significance (not withstanding adjustment for multiple testing) was for rs1901440 (neutropenia, p = 0.043) and rs11719165 (leukopenia, p = 0.049) where the risk alleles trended towards lower toxicity, contrasting with previous study findings. Risk alleles and higher risk scores were more common among our patients. We conclude that the genetic variants do not apply to Swedish patients treated with gemcitabine/carboplatin. However, they can still be important in other populations and cohorts, especially in a gemcitabine monotherapy setting, where the causal genetic variation might influence myelosuppressive ADRs.
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Affiliation(s)
- Niclas Björn
- Division of Clinical Chemistry and Pharmacology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Ingrid Jakobsen
- Division of Clinical Chemistry and Pharmacology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.,Department of Laboratory Medicine, Örebro University Hospital, Örebro, Sweden
| | - Chihiro Udagawa
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan
| | - Eva Brandén
- Department of Respiratory Medicine, Gävle Hospital, Gävle, Sweden.,Centre for Research and Development, Uppsala University/Region Gävleborg, Gävle, Sweden
| | - Hirsh Koyi
- Department of Respiratory Medicine, Gävle Hospital, Gävle, Sweden.,Centre for Research and Development, Uppsala University/Region Gävleborg, Gävle, Sweden
| | - Rolf Lewensohn
- Thoracic Oncology Unit, Tema Cancer, Karolinska University Hospital, and Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Luigi De Petris
- Thoracic Oncology Unit, Tema Cancer, Karolinska University Hospital, and Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Hitoshi Zembutsu
- Department of Clinical Genomics, National Cancer Center Research Institute, Tokyo, Japan
| | - Henrik Gréen
- Division of Clinical Chemistry and Pharmacology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.,Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden
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Åstrand A, Vikingsson S, Jakobsen I, Björn N, Kronstrand R, Gréen H. Activation of the μ-opioid receptor by alicyclic fentanyls: Changes from high potency full agonists to low potency partial agonists with increasing alicyclic substructure. Drug Test Anal 2020; 13:169-174. [PMID: 32749741 PMCID: PMC7891621 DOI: 10.1002/dta.2906] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 07/14/2020] [Accepted: 07/31/2020] [Indexed: 12/12/2022]
Abstract
Fentanyl analogs represent an important group of new psychoactive substances and knowing their efficacy and potency might assist in interpreting observed concentrations. The potency of fentanyl analogs can be estimated from in vitro studies and can be used to establish structure–activity relationships. In this study, recombinant CHO‐K1 cells (AequoScreen) expressing the human μ‐opioid receptor were used to establish dose–response curves via luminescent analysis for cyclopropyl‐, cyclobutyl‐, cyclopentyl‐, cyclohexyl‐, and 2,2,3,3‐tetramethylcyclopropylfentanyl (TMCPF), on three separate occasions, using eight different concentrations in an eight‐fold serial dilution in triplicates starting at ~60 μM. Fentanyl was used as a full agonist reference while morphine and buprenorphine were included for comparison. Cyclopropylfentanyl (EC50 = 4.3 nM), cyclobutylfentanyl (EC50 = 6.2 nM), and cyclopentylfentanyl (EC50 = 13 nM) were full agonists slightly less potent than fentanyl (EC50 = 1.7 nM). Cyclohexylfentanyl (EC50 = 3.1 μM, efficacy 48%) and TMCPF (EC50 = 1.5 μM, efficacy 65%) were partial agonists less potent than morphine (EC50 = 430 nM). Based on the results, cyclopropyl‐, cyclobutyl‐, and cyclopentylfentanyl would be expected to induce intoxication or cause fatal poisonings at similar concentrations to fentanyl, while the toxic or fatal concentrations of cyclohexylfentanyl and TMCPF would be expected to be much higher.
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Affiliation(s)
- Anna Åstrand
- Division of Drug Research, Department of Biomedical and Clinical Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Svante Vikingsson
- Division of Drug Research, Department of Biomedical and Clinical Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden.,Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden
| | - Ingrid Jakobsen
- Division of Drug Research, Department of Biomedical and Clinical Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden.,Department of Laboratory Medicine, Örebro University Hospital, Örebro, Sweden
| | - Niclas Björn
- Division of Drug Research, Department of Biomedical and Clinical Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Robert Kronstrand
- Division of Drug Research, Department of Biomedical and Clinical Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden.,Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden
| | - Henrik Gréen
- Division of Drug Research, Department of Biomedical and Clinical Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden.,Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden
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Malmström A, Łysiak M, Åkesson L, Jakobsen I, Mudaisi M, Milos P, Hallbeck M, Fomichov V, Broholm H, Grunnet K, Poulsen HS, Bratthäll C, Strandeus M, Papagiannopoulou A, Stenmark-Askmalm M, Green H, Söderkvist P. ABCB1 single-nucleotide variants and survival in patients with glioblastoma treated with radiotherapy concomitant with temozolomide. Pharmacogenomics J 2019; 20:213-219. [PMID: 31624332 DOI: 10.1038/s41397-019-0107-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 09/09/2019] [Accepted: 10/02/2019] [Indexed: 01/10/2023]
Abstract
Standard treatment for glioblastoma (GBM) patients is surgery and radiochemotherapy (RCT) with temozolomide (TMZ). TMZ is a substrate for ABCB1, a transmembrane drug transporter. It has been suggested that survival for GBM patients receiving TMZ is influenced by different single-nucleotide variants (SNV) of ABCB1. We therefore examined SNV:s of ABCB1, namely 1199G>A, 1236C>T, 2677G>T/A, and 3435C>T and correlated to survival for GBM patients receiving RCT. In a pilot cohort (97 patients) a significant correlation to survival was found for SNV 1199G>A, with median OS for variant G/G patients being 18.2 months versus 11.5 months for A/G (p = 0.012). We found no correlation to survival for the other SNV:s. We then expanded the cohort to 179 patients (expanded cohort) and also included a confirmatory cohort (49 patients) focusing on SNV 1199G>A. Median OS for G/G versus A/G plus A/A was 15.7 and 11.5 months, respectively (p = 0.085) for the expanded cohort and 13.8 versus 16.8 months (p = 0.19) for the confirmatory. In conclusion, in patients with GBM receiving RCT with TMZ, no correlation with survival was found for the SNV:s 1236C>T, 2677G>T/A, and 3435C>T of ABCB1. Although the SNV 1199G>A might have some impact, a clinically significant role could not be confirmed.
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Affiliation(s)
- Annika Malmström
- Department of Advanced Home Care, Linköping University, Linköping, Sweden. .,Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.
| | - Malgorzata Łysiak
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Lisa Åkesson
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.,Regional Cancer Center South East, Region Östergötland, Linköping, Sweden
| | - Ingrid Jakobsen
- Division of Drug Research, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden
| | - Munila Mudaisi
- Department of Oncology, Linköping University, Linköping, Sweden
| | - Peter Milos
- Department of Neurosurgery, Linköping University, Linköping, Sweden
| | - Martin Hallbeck
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.,Department of Clinical Pathology, Linköping University, Linköping, Sweden
| | - Victoria Fomichov
- Centre for Organizational Support and Development, Region Östergötland, Linköping University, Linköping, Sweden
| | - Helle Broholm
- Department of Pathology, Copenhagen University Hospital, Copenhagen, Denmark
| | - Kirsten Grunnet
- Department of Radiation Biology, Copenhagen University Hospital, Copenhagen, Denmark
| | - Hans Skovgaard Poulsen
- Department of Radiation Biology, Copenhagen University Hospital, Copenhagen, Denmark.,Section for Neuro-Oncology, Copenhagen University Hospital, Copenhagen, Denmark
| | | | | | - Angeliki Papagiannopoulou
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.,Department of Clinical Pathology, Linköping University, Linköping, Sweden
| | - Marie Stenmark-Askmalm
- Department of Clinical Genetics, University and Regional Laboratories, Skåne University Hospital, Lund University, Lund, Sweden
| | - Henrik Green
- Division of Drug Research, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.,Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden
| | - Peter Söderkvist
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
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de Boulois HD, Joner EJ, Leyval C, Jakobsen I, Chen BD, Roos P, Thiry Y, Rufyikiri G, Delvaux B, Declerck S. Role and influence of mycorrhizal fungi on radiocesium accumulation by plants. J Environ Radioact 2008; 99:785-800. [PMID: 18055077 DOI: 10.1016/j.jenvrad.2007.10.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/18/2007] [Indexed: 05/25/2023]
Abstract
This review summarizes current knowledge on the contribution of mycorrhizal fungi to radiocesium immobilization and plant accumulation. These root symbionts develop extended hyphae in soils and readily contribute to the soil-to-plant transfer of some nutrients. Available data show that ecto-mycorrhizal (ECM) fungi can accumulate high concentration of radiocesium in their extraradical phase while radiocesium uptake and accumulation by arbuscular mycorrhizal (AM) fungi is limited. Yet, both ECM and AM fungi can transport radiocesium to their host plants, but this transport is low. In addition, mycorrhizal fungi could thus either store radiocesium in their intraradical phase or limit its root-to-shoot translocation. The review discusses the impact of soil characteristics, and fungal and plant transporters on radiocesium uptake and accumulation in plants, as well as the potential role of mycorrhizal fungi in phytoremediation strategies.
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Affiliation(s)
- H Dupré de Boulois
- Université catholique de Louvain, Unité de Microbiologie, Croix du Sud 3, 1348 Louvain-la-Neuve, Belgium
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6
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de Boulois HD, Joner EJ, Leyval C, Jakobsen I, Chen BD, Roos P, Thiry Y, Rufyikiri G, Delvaux B, Declerck S. Impact of arbuscular mycorrhizal fungi on uranium accumulation by plants. J Environ Radioact 2008; 99:775-784. [PMID: 18069098 DOI: 10.1016/j.jenvrad.2007.10.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/18/2007] [Indexed: 05/25/2023]
Abstract
Contamination by uranium (U) occurs principally at U mining and processing sites. Uranium can have tremendous environmental consequences, as it is highly toxic to a broad range of organisms and can be dispersed in both terrestrial and aquatic environments. Remediation strategies of U-contaminated soils have included physical and chemical procedures, which may be beneficial, but are costly and can lead to further environmental damage. Phytoremediation has been proposed as a promising alternative, which relies on the capacity of plants and their associated microorganisms to stabilize or extract contaminants from soils. In this paper, we review the role of a group of plant symbiotic fungi, i.e. arbuscular mycorrhizal fungi, which constitute an essential link between the soil and the roots. These fungi participate in U immobilization in soils and within plant roots and they can reduce root-to-shoot translocation of U. However, there is a need to evaluate these observations in terms of their importance for phytostabilization strategies.
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Affiliation(s)
- H Dupré de Boulois
- Université catholique de Louvain, Unité de Microbiologie, Croix du Sud 3, 1348 Louvain-la-Neuve, Belgium
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7
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Joner EJ, Roos P, Jansa J, Frossard E, Leyval C, Jakobsen I. No significant contribution of arbuscular mycorrhizal fungi to transfer of radiocesium from soil to plants. Appl Environ Microbiol 2004; 70:6512-7. [PMID: 15528513 PMCID: PMC525231 DOI: 10.1128/aem.70.11.6512-6517.2004] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2004] [Accepted: 06/22/2004] [Indexed: 11/20/2022] Open
Abstract
The diffuse pollution by fission and activation products following nuclear accidents and weapons testing is of major public concern. Among the nuclides that pose a serious risk if they enter the human food chain are the cesium isotopes 137Cs and 134Cs (with half-lives of 30 and 2 years, respectively). The biogeochemical cycling of these isotopes in forest ecosystems is strongly affected by their preferential absorption in a range of ectomycorrhiza-forming basidiomycetes. An even more widely distributed group of symbiotic fungi are the arbuscular mycorrhizal fungi, which colonize most herbaceous plants, including many agricultural crops. These fungi are known to be more efficient than ectomycorrhizas in transporting mineral elements from soil to plants. Their role in the biogeochemical cycling of Cs is poorly known, in spite of the consequences that fungal Cs transport may have for transfer of Cs into the human food chain. This report presents the first data on transport of Cs by these fungi by use of radiotracers and compartmented growth systems where uptake by roots and mycorrhizal hyphae is distinguished. Independent experiments in three laboratories that used different combinations of fungi and host plants all demonstrated that these fungi do not contribute significantly to plant uptake of Cs. The implications of these findings for the bioavailability of radiocesium in different terrestrial ecosystems are discussed.
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Affiliation(s)
- E J Joner
- LIMOS-CNRS, UMR 7137 CNRS-UHP, Faculty of Sciences, H. Poincaré University Nancy 1, Vandoeuvre-les-Nancy, France.
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Nielsen JS, Joner EJ, Declerck S, Olsson S, Jakobsen I. Phospho-imaging as a tool for visualization and noninvasive measurement of P transport dynamics in arbuscular mycorrhizas. New Phytol 2002; 154:809-819. [PMID: 33873457 DOI: 10.1046/j.1469-8137.2002.00412.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
• A new method is described for monitoring hyphal 32 P transport in compartmented, monoxenic mycorrhizal root cultures. Nondestructive time-course measurements of P transport in hyphae were obtained by capturing digital autoradiograms on P-imaging screens, and comparing with growth observed by optical scanning. 32 P distribution measured by densitometry on the day of harvest closely agreed with values obtained by liquid scintillation counting after destructive harvest. • Virtually all labeled PO4 was absorbed by arbuscular mycorrhizal (AM) hyphae, but transfer to the roots appeared to be incomplete. P transport was not unidirectional towards the roots, as 32 P was also transported from the root compartment to the hyphal compartment. Net P flux rates were calculated for hyphae crossing between compartments, taking bidirectional flow into account. • Amounts of transported P were poorly correlated with extra-radical hyphal length and root d. wt, but highly correlated with the number of hyphae crossing the barrier separating the two compartments. Such correlations were highest when only hyphae with detectable protoplasmic streaming were considered. • The method was tested using radiolabeled P sources, H2 PO4 - and cytidine triphosphate (CTP), and the AM fungi, Glomus intraradices and G. proliferum. Fungal transport of 32 P from CTP was much slower than from PO4 for both fungi.
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Affiliation(s)
- J S Nielsen
- Risø National Laboratory, DK-4000 Roskilde, Denmark
| | - E J Joner
- Centre de Pedologique Biologique - CNRS, F-54501 Vandoeuvre-les-Nancy, France
| | - S Declerck
- Universite Catholique de Louvain, 1348 Louvain-La-Neuve, Belgium
| | - S Olsson
- The Royal Veterinary and Agricultural University, DK-1870 Frederiksberg, Denmark
| | - I Jakobsen
- Risø National Laboratory, DK-4000 Roskilde, Denmark
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Gavito ME, Curtis PS, Mikkelsen TN, Jakobsen I. Interactive effects of soil temperature, atmospheric carbon dioxide and soil N on root development, biomass and nutrient uptake of winter wheat during vegetative growth. J Exp Bot 2001; 52:1913-23. [PMID: 11520880 DOI: 10.1093/jexbot/52.362.1913] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Nutrient requirements for plant growth are expected to rise in response to the predicted changes in CO(2) and temperature. In this context, little attention has been paid to the effects of soil temperature, which limits plant growth at early stages in temperate regions. A factorial growth-room experiment was conducted with winter wheat, varying soil temperature (10 degrees C and 15 degrees C), atmospheric CO(2) concentration (360 and 700 ppm), and N supply (low and high). The hypothesis was that soil temperature would modify root development, biomass allocation and nutrient uptake during vegetative growth and that its effects would interact with atmospheric CO(2) and N availability. Soil temperature effects were confirmed for most of the variables measured and 3-factor interactions were observed for root development, plant biomass components, N-use efficiency, and shoot P content. Importantly, the soil temperature effects were manifest in the absence of any change in air temperature. Changes in root development, nutrient uptake and nutrient-use efficiencies were interpreted as counterbalancing mechanisms for meeting nutrient requirements for plant growth in each situation. Most variables responded to an increase in resource availability in the order: N supply >soil temperature >CO(2).
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Affiliation(s)
- M E Gavito
- Department of Plant Research, Risø National Laboratory, PO Box 49, DK-4000 Roskilde, Denmark
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Abstract
• Variation in phosphate uptake capacity is reported here for natural communities of arbuscular mycorrhizal fungi associated with annual pasture plants. • Tests were made of methodology for quantifying phosphate uptake by hyphae associated with clover in soil cores from pastures containing different morphotypes of the fungi. This provided a direct measure of the phosphate uptake capacity of hyphae from 32 P-labelled soil in a root-free mesh bag inserted into the centre of intact soil cores. • Bicarbonate-extractable phosphorus in the soils ranged from very deficient to close to adequate for plant growth. Uptake of 32 P was related to an estimate of the length of hyphae formed in four of the five soils, but not to either the length or the proportion of roots colonized. In the fifth soil type, phosphate uptake by hyphae was negligible. • Phosphate uptake by natural communities of arbuscular mycorrhizal fungi in intact soil cores can be assessed directly, and is shown to be highly variable. The experimental approach could be applied widely for field investigations of phosphate uptake by hyphal networks.
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Affiliation(s)
- I Jakobsen
- Plant Biology and Biogeochemistry Department, Risø National Laboratory, DK-4000 Roskilde, Denmark
| | - C Gazey
- Soil Science and Plant Nutrition, Faculty of Agriculture, The University of Western Australia, Nedlands, WA 6907, Australia
- Present address: Plant Research and Development Services, Agriculture Western Australia, Baron-Hay Court, South Perth, WA 6151, Australia
| | - L K Abbott
- Soil Science and Plant Nutrition, Faculty of Agriculture, The University of Western Australia, Nedlands, WA 6907, Australia
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Gavito ME, Curtis PS, Mikkelsen TN, Jakobsen I. Atmospheric CO(2) and mycorrhiza effects on biomass allocation and nutrient uptake of nodulated pea (Pisum sativum L.) plants. J Exp Bot 2000; 51:1931-8. [PMID: 11113171 DOI: 10.1093/jexbot/51.352.1931] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The effect of ambient and elevated atmospheric CO(2) on biomass partitioning and nutrient uptake of mycorrhizal and non-mycorrhizal pea plants grown in pots in a controlled environment was studied. The hypothesis tested was that mycorrhizae would increase C assimilation by increasing photosynthetic rates and reduce below-ground biomass allocation by improving nutrient uptake. This effect was expected to be more pronounced at elevated CO(2) where plant C supply and nutrient demand would be increased. The results showed that mycorrhizae did not interact with atmospheric CO(2) concentration in the variables measured. Mycorrhizae did not affect photosynthetic rates, had no effect on root weight or root length density and almost no effect on nutrient uptake, but still significantly increased shoot weight and reduced root/shoot ratio at harvest. Elevated CO(2) increased photosynthetic rates with no evidence for down-regulation, increased shoot weight and nutrient uptake, had no effect on root weight, and actually reduced root/shoot ratio at harvest. Non-mycorrhizal plants growing at both CO(2) concentrations had lower shoot weight than mycorrhizal plants with similar nutritional status and photosynthetic rates. It is suggested that the positive effect of mycorrhizal inoculation was caused by an enhanced C supply and C use in mycorrhizal plants than in non-mycorrhizal plants. The results indicate that plant growth was not limited by mineral nutrients, but partially source and sink limited for carbon. Mycorrhizal inoculation and elevated CO(2) might have removed such limitations and their effects on above-ground biomass were independent, positive and additive.
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Affiliation(s)
- M E Gavito
- Plant Biology and Biogeochemistry Department, Riso National Laboratory, PO Box 49, DK-4000 Roskilde, Denmark.
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Abstract
The receptor of a T lymphocyte (TCR) recognizes nonself antigens in the company of major histocompatibility complex (MHC) molecules presented to it by the antigen-presenting cell. The variable region of TCR is encoded by either a concatenation of variable region (TCR-V), diversity region (TCR-D), and joining region (TCR-J) genes, or a concatenation of TCR-V and TCR-J genes. The TCR-V genes exist as a multigene family in vertebrate species. Here we study the evolutionary relationships of TCR-V genes from humans, sheep, cattle, rabbits, mice, and chicken. These six species can be classified into two groups according to the frequency of gamma(delta) T-cells in their peripheral T-cell populations. The "gamma(delta) low" group of species includes humans and mice, in which gamma(delta)T-cells constitute very limited portion of the T-cell population. The "gamma(delta) high" group includes sheep, cattle, rabbits, and chicken, in which gamma(delta) T-cells comprise up to 60% of the T-cell population. Here, we compiled TCR-V sequences from the six species and conducted a phylogenetic analysis. We identified various TCR-V gene subgroups based on the analysis. We found that humans and mice have representatives from nearly all of the subgroups identified, while other species have lost subgroups to different extent. Therefore, the gamma(delta) low species have a high degree of diversity of TCR-V genes, while gamma(delta) high species all have limited diversity of TCR-V genes. This pattern is similar to that found for immunoglobulin variable region (IGV) genes.
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Affiliation(s)
- C Su
- Institute of Molecular Evolutionary Genetics and Department of Biology, The Pennsylvania State University, University Park 16802, USA.
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Olsson PA, Baath E, Jakobsen I. Phosphorus effects on the mycelium and storage structures of an arbuscular mycorrhizal fungus as studied in the soil and roots by analysis of Fatty Acid signatures. Appl Environ Microbiol 1997; 63:3531-8. [PMID: 16535691 PMCID: PMC1389247 DOI: 10.1128/aem.63.9.3531-3538.1997] [Citation(s) in RCA: 152] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The distribution of an arbuscular mycorrhizal (AM) fungus between soil and roots, and between mycelial and storage structures, was studied by use of the fatty acid signature 16:1(omega)5. Increasing the soil phosphorus level resulted in a decrease in the level of the fatty acid 16:1(omega)5 in the soil and roots. A similar decrease was detected by microscopic measurements of root colonization and of the length of AM fungal hyphae in the soil. The fatty acid 16:1(omega)5 was estimated from two types of lipids, phospholipids and neutral lipids, which mainly represent membrane lipids and storage lipids, respectively. The numbers of spores of the AM fungus formed in the soil correlated most closely with neutral lipid fatty acid 16:1(omega)5, whereas the hyphal length in the soil correlated most closely with phospholipid fatty acid 16:1(omega)5. The fungal neutral lipid/phospholipid ratio in the extraradical mycelium was positively correlated with the level of root infection and thus decreased with increasing applications of P. The neutral lipid/phospholipid ratio indicated that at high P levels, less carbon was allocated to storage structures. At all levels of P applied, the major part of the AM fungus was found to be present outside the roots, as estimated from phospholipid fatty acid 16:1(omega)5. The ratio of extraradical biomass/intraradical biomass was not affected by the application of P, except for a decrease at the highest level of P applied.
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Larsen J, Thingstrup I, Jakobsen I, Rosendahl S. Benomyl inhibits phosphorus transport but not fungal alkaline phosphatase activity in a Glomus-cucumber symbiosis. New Phytol 1996; 132:127-133. [PMID: 33863061 DOI: 10.1111/j.1469-8137.1996.tb04518.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Short-term effects of benomyl on the arbuscular mycorrhizal fungus Glomus caledonium (Nicol. & Gerd.) Trappe and Gerdeman associated with Cucumis sativus L. were studied by measuring effects on fungal P transport and on fungal alkaline phosphatase activity. Mycorrhizal plants were grown in three compartment systems where nylon mesh was used to separate n root-free hyphal compartment (HC) and a root + hyphal compartment(RHC) from The main root compartment (RC). Non-mycorrhizal control plants were grown in similar growth units. After 6 wk benomyl was applied to the plants in three ways: as soil drenches to RHC or HC, or as u spray to the leaves. Benomyl was added in three concentrations. Equal amounts of 32 P and 33 P were added to the HC and to the RHC respectively, immediately after the application of benomyl. Plants were harvested 4-6 d later. Hyphal transport of 32 P from the HC was inhibited when benomyl was applied to the HC at 10 μg g-1 soil, whereas the uptake of 32 P from RHC I roots + hyphae) was reduced only at the highest dose of application to the RHC (100 μ g g-1 soil). In contrast to the marked reduction of benomyl on fungal P transport, the activity of fungal alkaline phosphatase inside the roots was unaffected by benomyl.
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Affiliation(s)
- J Larsen
- Plant Nutrition, Environmental Science and Technology Department, Rise National Laboratory, P.O. Box 49, DK-4000 Roskilde, Denmark
| | - I Thingstrup
- Department of Mycology, University of Copenhagen, Øster Farimagsgade 2D, DK-1353 Copenhagen, Denmark
| | - I Jakobsen
- Plant Nutrition, Environmental Science and Technology Department, Rise National Laboratory, P.O. Box 49, DK-4000 Roskilde, Denmark
| | - S Rosendahl
- Department of Mycology, University of Copenhagen, Øster Farimagsgade 2D, DK-1353 Copenhagen, Denmark
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Abstract
Tumours with necrotic regions have an inadequate blood supply and are expected to differ from well-vascularised tumours in response to treatment. The purpose of the present work was to investigate whether proton magnetic resonance imaging (MRI) might be used to detect necrotic regions in tumours. MR images and histological sections from individual tumours of three different amelanotic human melanoma xenograft lines (BEX-t, HUX-t, SAX-t) were analysed in pairs. MRI was performed at 1.5 T using two spin-echo pulse sequences, one with a repetition time (TR) of 600 ms and echo times (TEs) of 20, 40, 60 and 80 ms and the other with a TR of 2000 ms and TEs of 20, 40, 60 and 80 ms. Spin-lattice relaxation time (T1), spin-spin relaxation time (T2) and proton density (N0) were calculated for each volume element corresponding to a pixel. Synthetic MR images, pure T1, T2 and N0 images and spin-echo images with chosen values for TR and TE were generated from these data. T1, T2 and N0 distributions of tumour subregions, corresponding to necrotic regions and regions of viable tissue as defined by histological criteria, were also generated. T1 and T2 were significantly shorter in the necrotic regions than in the regions of viable tissue in all tumours. These differences were sufficiently large to allow the generation of synthetic spin-echo images showing clear contrast between necrosis and viable tissue. Maximum contrast was achieved with TRs within the range 2800-4000 ms and TEs within the range 160-200 ms. Necrotic tissue could also be distinguished from viable tissue in pure T1 and T2 images. Consequently, the possibility exists that MRI might be used for detection of necrotic regions in tumours and hence for prediction of tumour treatment response.
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Affiliation(s)
- I Jakobsen
- Institute for Cancer Research, Norwegian Radium Hospital, Montebello, Oslo
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Abstract
Proton T1 and T2 differ substantially between tumors, but the tumor properties causing heterogeneity in T1 and T2 have not been fully recognized. The purpose of the study reported here was to investigate whether differences in T1 and T2 between tumors are mainly a consequence of differences in the fractional volume of the extracellular compartment. The study was performed using a single human tumor xenograft line showing large naturally occurring intratumor heterogeneity in the size of the extracellular compartment. The size of the extracellular compartment was calculated from the volume and the density of the tumor cells. Cell volume was measured by an electronic particle counter. Cell density was determined by stereological analysis of histological preparations. T1 and T2 were measured by MRI in vivo both in the absence and presence of Gd-DTPA. Two spin-echo pulse sequences were used, one with a repetition time (TR) of 600 ms and echo times (TEs) of 20, 40, 60, and 80 ms and the other with a TR of 2,000 ms and TEs of 20, 40, 60, and 80 ms. Measurements of T1 and T2 in the presence of Gd-DTPA were performed in a state of semi-equilibrium between uptake and clearance of Gd-DTPA. MR-images and histological preparations of tumor subregions homogeneous in extracellular volume were analysed in pairs. The extracellular volume differed between tumor subregions from 5 to 70%. T1 and T2 measured in the absence of Gd-DTPA differed between tumor subregions by a factor of approximately 1.5 and increased with increasing extracellular volume. The relative decrease in T1 caused by Gd-DTPA, represented by (T1 control-T1 Gd-DTPA)/T1 control, also increased with increasing extracellular volume.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- I Jakobsen
- Department of Biophysics, Norwegian Radium Hospital, Montebello, Oslo, Norway
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Johansen A, Jakobsen I, Jensen ES. Hyphal transport of 15 N-labelled nitrogen by a vesicular-arbuscular mycorrhizal fungus and its effect on depletion of inorganic soil N. New Phytol 1992; 122:281-288. [PMID: 33873984 DOI: 10.1111/j.1469-8137.1992.tb04232.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Hyphal transport of nitrogen from a 15 N-labelled ammonium source by a VA-mycorrhizal fungus was studied under controlled experimental conditions. Cucumis sativus L. cv. Aminex (F1 hybrid) was grown alone or together with Glomus intraradices Schenck and Smith in containers with a hyphal compartment separated from the rooting medium by a fine nylon mesh. Lateral movement of the applied 15 N towards the roots was minimized by using a nitrification inhibitor (N-serve) and a hyphal buffer compartment. Recovery of 15 N by mycorrhizal and non-mycorrhizal plants was 6 and 0%, respectively, after a labelling period of 23 days. The corresponding figures, without N-serve added, were 4 and 7%. A prolongation of the labelling period by 8 days (N-serve applied) resulted in an increase in the 15 N recovery by mycorrhizal plants to 30% of the applied 15 N. Non-mycorrhizal plants contained only traces of 15 N. The external hyphae depleted the soil in the hyphal compartment efficiently for inorganic N. In contrast, hyphal compartments of control containers still contained considerable amounts of inorganic N. The 15 N assimilated by the external hyphae in one hyphal compartment was not translocated in significant amounts to the external hyphae in another hyphal compartment. The possible implication of this for inter-plant N transfer by VA hyphal connections is discussed.
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Affiliation(s)
- A Johansen
- Plant Biology Section, Environmental Science and Technology Department, Rise National Laboratory, DK-4000 Roskilde, Denmark
| | - I Jakobsen
- Plant Biology Section, Environmental Science and Technology Department, Rise National Laboratory, DK-4000 Roskilde, Denmark
| | - E S Jensen
- Plant Biology Section, Environmental Science and Technology Department, Rise National Laboratory, DK-4000 Roskilde, Denmark
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Jakobsen I. VESICULAR-ARBUSCULAR MYCORRHIZA IN FIELD-GROWN CROPS: III. MYCORRHIZAL INFECTION AND RATES OF PHOSPHORUS INFLOW IN PEA PLANTS. New Phytol 1986; 104:573-581. [PMID: 33873865 DOI: 10.1111/j.1469-8137.1986.tb00657.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The importance of vesicular-arbuscular mycorrhiza (VAM) and P fertilizer for P nutrition and dry matter production in field peas (Pisum sativum L.) was studied in moderately P-deficient soil. Half of the experimental plots were fumigated to reduce the level of VAM infection. Shoots and 0 to 30 cm soil cores were sampled on three occasions. An extensive VAM infection was rapidly established in untreated soil, whereas infection levels were low in fumigated soil. Root growth responded to fumigation by increased root length and decreased root diameter. Fumigation reduced the P content in shoots considerably, and correspondingly the mean rates of P inflow per unit root length were 60% lower in fumigated than in untreated soil during flowering. These effects of fumigation were ascribed to the low levels of VAM infection in fumigated soil. The production of dry matter was not decreased accordingly in fumigated plots, although both it and P uptake were increased by adding P fertilizer. The possible reasons for this discrepancy are discussed. A supplementary survey on infection development at five other field sites showed that peas are extensively colonized by VAM fungi, even in soils where a standard procedure is being used. These results indicate that VAM is of major importance to P uptake by the field-grown pea.
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Affiliation(s)
- I Jakobsen
- Agricultural Research Department, Risø National Laboratory, DK-4000 Roskilde, Denmark
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Jakobsen I, Larsen M, Lindvig K, Møller M. [Long-term ECG registration. Practical experiences]. Ugeskr Laeger 1982; 144:1149-52. [PMID: 7112698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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