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Wahlström H, Lindberg A, Lindh J, Wallensten A, Lindqvist R, Plym-Forshell L, Osterman Lind E, Ågren EO, Widgren S, Carlsson U, Christensson D, Cedersmyg M, Lindström E, Olsson GE, Hörnfeldt B, Barragan A, Davelid C, Hjertqvist M, Elvander M. Investigations and actions taken during 2011 due to the first finding of Echinococcus multilocularis in Sweden. Euro Surveill 2012; 17. [DOI: 10.2807/ese.17.28.20215-en] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Echinococcus multilocularis is a parasite that can cause alveolar echinococcosis disease. After the first positive finding of E. multilocularis in Sweden in 2011, a consulting group with representatives from relevant authorities was summoned. In this group, all relevant information was shared, strategies for information dissemination and any actions to be taken due to the finding of E. multilocularis were discussed and decided. The present paper describes the actions taken during 2011 and the results thereof, including surveillance in animals, risk assessment for humans to become infected and recommendations given to the public. Further discussion about whether the parasite was introduced, and if so, how, as well as possible future development of the infection in animals and humans in Sweden and future actions are included.
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Sävmarker J, Lindh J, Nilsson P, Sjöberg PJR, Larhed M. Oxidative Heck Reactions using Aryltrifluoroborates and Aryl N-Methyliminodiacetic Acid (MIDA) Boronates. ChemistryOpen 2012; 1:140-6. [PMID: 24551502 PMCID: PMC3922452 DOI: 10.1002/open.201200007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Indexed: 11/30/2022] Open
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Emilsson S, Svensk AC, Tavelin B, Lindh J. Support group participation during the post-operative radiotherapy period increases levels of coping resources among women with breast cancer. Eur J Cancer Care (Engl) 2012; 21:591-8. [PMID: 22487421 DOI: 10.1111/j.1365-2354.2012.01343.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
r Being diagnosed with breast cancer is a traumatic experience that can elevate levels of distress and cause depletion of coping resources in many of the disease's victims. This non-randomised case-control study among breast cancer patients undergoing radiotherapy indicates that participation in a support group that focuses on communication and mutual sharing between its member's has positive effects and increases levels of coping resources assessed with the Coping Resources Inventory (CRI). Results of the CRI showed a significant difference between the study group and control group in the social domain at the second occasion of measurement (P= 0.007) and in the emotional domain at the third occasion (P= 0.028). Within the study group, over time, increased levels of coping resources reached significant levels concerning the emotional domain at the second occasion (P= 0.025). Conversely, coping resources were decreased in the same domain within the control group over time, at the third occasion (P= 0.053). Additionally, anxiety and depression were assessed using the Hospital Anxiety and Depression Scale, showing no difference between the groups. This study shows that participation in a support group during post-operative radiotherapy can be socially and emotionally strengthening because of the opportunity for the patients to mutually share experiences.
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Lindh J, Söderkvist P, Fredrikson M, Hosseininia S, Tondel M, Persson B, Vrethem M. Polymorphisms of GSTT1, GSTM1, and EPHX genotypes in patients with cryptogenic polyneuropathy: a case-control study. Brain Behav 2011; 1:135-41. [PMID: 22399093 PMCID: PMC3236538 DOI: 10.1002/brb3.26] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 09/02/2011] [Accepted: 09/12/2011] [Indexed: 11/12/2022] Open
Abstract
The aim of this study was to analyze whether polymorphisms for the null alleles of Glutathione S-Transferase Mu-1 (GSTM1), Glutathione S-Transferase Theta-1 (GSTT1), and a low-activity genetic variation of epoxide hydrolase exon three (EPHX*3) affect the risk of developing polyneuropathy. The enzymes of these genes are important in the metabolism of toxic compounds. Seventy-nine patients with cryptogenic polyneuropathy (equivalent to chronic idiopathic axonal neuropathy) and 398 controls were tested for the genetic polymorphism. Medical records were reviewed to collect data regarding clinical findings at diagnosis, and exposure data was collected via questionnaires. The odds ratios (ORs) for the null forms of GSTM1 and GSTT1 and the normal activity YY form of EPHX*3 were close to one except GSTT1, which reached 1.86. The highest risk of polyneuropathy was found in smokers with GSTT1 null, who had a 3.7 times increased risk. Interactions between genes were analyzed and confirmed the increased OR for GSTT1, which was strongest if the patients had the low-activity HH form of EPHX*3 (OR 2.37). Our hypothesis is that the GSTT1 null polymorphism may be related to an impaired metabolism of toxic substances that could lead to nerve damage in the peripheral nervous system.
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Sävmarker J, Lindh J, Nilsson P. Deoxybenzoins from Stille carbonylative cross-couplings using molybdenum hexacarbonyl. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.10.115] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Lindh J, Sjöberg PJR, Larhed M. Synthesis of Aryl Ketones by Palladium(II)-Catalyzed Decarboxylative Addition of Benzoic Acids to Nitriles. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201003009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Lindh J, Tondel M, Persson B, Vrethem M. Health-related quality of life in patients with cryptogenic polyneuropathy compared with the general population. Disabil Rehabil 2010; 33:617-23. [PMID: 20690857 DOI: 10.3109/09638288.2010.505996] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To evaluate the quality of life (QOL) in patients with cryptogenic polyneuropathy. METHOD Two validated instruments (SF-36 and EQ-5D) were sent to 86 patients with a 72% response rate (44 men, 18 women). As reference, 2721 individuals (1292 men, 1429 women; 59% response rate) from the general population responded to the same QOL instruments. RESULTS Compared to the general population, QOL was significantly more affected in patients with polyneuropathy concerning motor functions, with 42% of the patients reporting problems with walking, 7% having difficulties with washing and dressing, and 31% having problems with usual activities (work, study, household work, and family or leisure activities). The EQ-5D results showed that 85% of the patients were suffering from pain compared to 56% of the general population. Mental health was preserved among patients with polyneuropathy. Mobility was declining with increasing age in patients, but was not affected by disease duration. CONCLUSIONS Our study showed that patients with cryptogenic polyneuropathy have a lower QOL compared to the general population, although mental health scores did not differ between the groups. This information may be helpful when explaining the disease and its impact on newly diagnosed patients.
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Åberg O, Stevens M, Lindh J, Wallinder C, Hall H, Monazzam A, Larhed M, Långström B. Synthesis and evaluation of a 11C-labelled angiotensin II AT2 receptor ligand. J Labelled Comp Radiopharm 2010. [DOI: 10.1002/jlcr.1793] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Odell LR, Lindh J, Gustafsson T, Larhed M. Continuous Flow Palladium(II)-Catalyzed Oxidative Heck Reactions with Arylboronic Acids. European J Org Chem 2010. [DOI: 10.1002/ejoc.201000063] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Andaloussi M, Lindh J, Sävmarker J, Sjöberg PJR, Larhed M. Microwave-promoted palladium(II)-catalyzed C-P bond formation by using arylboronic acids or aryltrifluoroborates. Chemistry 2010; 15:13069-74. [PMID: 19856344 DOI: 10.1002/chem.200901473] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The first Pd(II)-catalyzed P arylation has been performed by using palladium acetate, the rigid bidentate ligand dmphen (dmphen=2,9-dimethyl-1,10-phenanthroline), and without the addition of base or acid. Couplings of arylboronic acids or aryl trifluoroborates with H-phosphonate dialkyl esters were conducted in 30 min with controlled microwave (MW) heating under non-inert conditions. Aryl phosphites were also synthesized at room temperature with atmospheric air as the sole reoxidant. The arylated phosphonates were isolated in 44-90 % yields. The excellent chemoselectivity of the method was illustrated in the synthesis of a Mycobacterium tuberculosis glutamine synthetase (MTB-GS) inhibitor. Online ESIMS was used to detect cationic palladium species in ongoing reactions directly, and a catalytic cycle has been proposed based on these results.
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Svensk AC, Oster I, Thyme KE, Magnusson E, Sjödin M, Eisemann M, Aström S, Lindh J. Art therapy improves experienced quality of life among women undergoing treatment for breast cancer: a randomized controlled study. Eur J Cancer Care (Engl) 2009; 18:69-77. [PMID: 19473224 DOI: 10.1111/j.1365-2354.2008.00952.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Women with breast cancer are naturally exposed to strain related to diagnosis and treatment, and this influences their experienced quality of life (QoL). The present paper reports the effect, with regard to QoL aspects, of an art therapy intervention among 41 women undergoing radiotherapy treatment for breast cancer. The women were randomized to an intervention group with individual art therapy sessions for 1 h/week (n = 20), or to a control group (n = 21). The WHOQOL-BREF and EORTC Quality of Life Questionnaire-BR23, were used for QoL assessment, and administrated on three measurement occasions, before the start of radiotherapy and 2 and 6 months later. The results indicate an overall improvement in QoL aspects among women in the intervention group. A significant increase in total health, total QoL, physical health and psychological health was observed in the art therapy group. A significant positive difference within the art therapy group was also seen, concerning future perspectives, body image and systemic therapy side effects. The present study provides strong support for the use of art therapy to improve QoL for women undergoing radiotherapy treatment for breast cancer.
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Lindh J, Sävmarker J, Nilsson P, Sjöberg PJR, Larhed M. Synthesis of styrenes by palladium(II)-catalyzed vinylation of arylboronic acids and aryltrifluoroborates by using vinyl acetate. Chemistry 2009; 15:4630-6. [PMID: 19274694 DOI: 10.1002/chem.200802744] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
One Heck of a reaction: Treatment of arylboronic acids or aryltrifluoroborates with vinyl acetate by using a palladium(II) catalyst gives the corresponding styrenes (see scheme). No palladium reoxidant is needed and the vinylation is performed under non-inert conditionsReactions of aromatic and heteroaromatic boronic acids or aryltrifluoroborate salts with vinyl acetate in the presence of a palladium(II) catalyst give the corresponding styrenes in good yields. This Heck reaction proceeds with microwave heating in less than 30 min at 140 degrees C in the absence of base and tolerates a variety of substituents. No palladium reoxidant is needed and the vinylation is performed under non-inert conditions. Mass spectrometry (electrospray ionization mass spectrometry (ESIMS) and tandem mass spectrometry (MS/MS)) was used to identify cationic palladium-containing complexes in ongoing reactions. The key intermediates that have been detected, together with experiments that used deuterated vinyl acetate, support the existence of catalytically active palladium hydride species, and that it is the arylation of ethylene, not vinyl acetate, which generates the styrene product. The mechanism of the reaction is discussed in terms of the palladium(II) intermediates mentioned above.
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Lindh J. Short episode of seizures in a newborn of a mother treated with levodopa/carbidopa/entacapone and bromocriptine. Mov Disord 2007; 22:1515. [PMID: 17486647 DOI: 10.1002/mds.21494] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Lindström I, Sundar N, Lindh J, Kironde F, Kabasa JD, Kwok OCH, Dubey JP, Smith JE. Isolation and genotyping of Toxoplasma gondii from Ugandan chickens reveals frequent multiple infections. Parasitology 2007; 135:39-45. [PMID: 17892617 DOI: 10.1017/s0031182007003654] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The genetic make-up of an infecting Toxoplasma gondii strain may be important for the outcome of infection and the risk of reactivation of chronic disease. In order to survey the distribution of different genotypes within an area, free-range chickens act as a good model species. In this study 85 chickens were used to investigate the prevalence, genotype and mouse virulence of T. gondii in Kampala, Uganda. Antibodies were detected in 40 chickens, of which 20 had MAT-titres of 1:20 or higher and were also positive by PCR. Genotyping of 5 loci (SAG1, SAG2, SAG3, BTUB and GRA6) showed that 6 strains belonged to genotype I, 8 to Type II and 1 to Type III. Five chickens had multiple infections; 3 individuals with Type I plus Type II and a further 2 harbouring Types I, II and III. Isolates were obtained from 9 chickens via bioassay in mice, 6 were Type II strains and 3 were from animals with mixed infection. This is the first set of African T. gondii strains to be genotyped at multiple loci and in addition to the 3 predominant lineages we found a small number of new polymorphisms and a high frequency of multiple infections.
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Lindh J, Enquist PA, Pilotti A, Nilsson P, Larhed M. Efficient Palladium(II) Catalysis under Air. Base-Free Oxidative Heck Reactions at Room Temperature or with Microwave Heating. J Org Chem 2007; 72:7957-62. [PMID: 17887706 DOI: 10.1021/jo701434s] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Scope and limitations of the base-free oxidative Heck reaction with arylboronic acids have been explored. Under our conditions, the dmphen-palladium(II)-catalyzed arylation proceeded with air or p-benzoquinone as reoxidants of palladium(0). We found that ambient temperature and mild aerobic conditions allow for the use of substrates sensitive to palladium(II)-catalyzed oxidation. Oxidative Heck couplings, employing different arylboronic acids, were smoothly and regioselectively conducted with both electron-rich and electron-poor olefins, providing high yields even with disubstituted butyl methacrylate, sensitive acrolein, and a vinylboronate ester. Controlled microwave processing was used to reduce reaction times from hours to minutes both in small scale and in 50 mmol scale batch processes.
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Garza D, Besier T, Johnston T, Rolston B, Schorsch A, Matheson G, Annerstedt C, Lindh J, Rydmark M. Use of a virtual human performance laboratory to improve integration of mathematics and biology in sports science curricula in Sweden and the United States. Stud Health Technol Inform 2007; 125:140-2. [PMID: 17377252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
New fields such as bioengineering are exploring the role of the physical sciences in traditional biological approaches to problems, with exciting results in device innovation, medicine, and research biology. The integration of mathematics, biomechanics, and material sciences into the undergraduate biology curriculum will better prepare students for these opportunities and enhance cooperation among faculty and students at the university level. We propose the study of sports science as the basis for introduction of this interdisciplinary program. This novel integrated approach will require a virtual human performance laboratory dual-hosted in Sweden and the United States. We have designed a course model that involves cooperative learning between students at Göteborg University and Stanford University, utilizes new technologies, encourages development of original research and will rely on frequent self-assessment and reflective learning. We will compare outcomes between this course and a more traditional didactic format as well as assess the effectiveness of multiple web-hosted virtual environments. We anticipate the grant will result in a network of original faculty and student research in exercise science and pedagogy as well as provide the opportunity for implementation of the model in more advance training levels and K-12 programs.
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Tondel M, Lindh J, Jonsson P, Vrethem M, Persson B. Occupational Determinants of Cryptogenic Polyneuropathy. Neuroepidemiology 2006; 26:187-94. [PMID: 16569935 DOI: 10.1159/000092405] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES The aim was to investigate different occupational and leisure time exposures as determinants for cryptogenic polyneuropathy. METHODS A case-referent study was conducted in Sweden including 232 cases of cryptogenic polyneuropathy 40-79 years of age at diagnosis who were enrolled from the out-patient neurology departments of 3 hospitals. From the population register 853 referents were randomly selected. Information on occupational and leisure time exposure was obtained from a postal questionnaire. The response rate was 71% for cases and for referents. Crude odds ratios (CORs) and logistic regression odds ratios (LORs) were calculated for exposures with 5 or more exposed cases and referents taken together. The reference category was defined as individuals unexposed to any of the occupational or leisure time risk factors in the questionnaire. RESULTS As expected, male sex and increasing age were significant determinants for cryptogenic polyneuropathy. Occupational exposures in men to Stoddard solvent, petrol exhausts, herbicides or hand and foot vibrations generated significantly increased CORs. LORs >3.50 were found in men for occupational exposure to sulphur dioxide, xylene, methyl ethyl ketone, herbicides and in women for occupational exposure to lead, nitrous oxide and insecticides. Only solvent exposure in leisure time remained significant in the regression analysis indicating that not only occupational exposures were of importance. Interactions between occupational and leisure time exposure were seen for several agents. CONCLUSIONS Several known determinants for polyneuropathy, from animal studies and case reports, were confirmed. New determinants were also indicated, i.e. sulphur dioxide, xylene and methyl ethyl ketone.
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Kristensen I, Karlsson M, Lindh J. 261 Distributed radiotherapy — the use of telemedicine as a tool for decision making in paediatric radiation oncology ? a report from SWPR. Radiother Oncol 2005. [DOI: 10.1016/s0167-8140(05)81238-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Lindh J, Tondel M, Osterberg A, Vrethem M. Cryptogenic polyneuropathy: clinical and neurophysiological findings. J Peripher Nerv Syst 2005; 10:31-7. [PMID: 15703016 DOI: 10.1111/j.1085-9489.2005.10106.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The purpose of this study was to describe the clinical and neurophysiological features of cryptogenic polyneuropathy in 168 patients in the neurological departments at three Swedish hospitals. The medical records of all patients aged 40-79 years with the diagnosis of cryptogenic polyneuropathy from 1993 to 2000 were analysed. One hundred and fourteen patients (68%) were men. The mean age at first symptom was 61 years and at diagnosis it was 64 years. Distal numbness (n = 115, 68%) was the most common symptom, but some patients complained of pain, pedal paresthesiae, and impairment of balance. The most common clinical findings were decreased or lost proprioception or sense of vibration (n = 135, 80%) and loss of ankle jerks (n = 131, 78%). Neurography in 139 patients showed mixed sensorimotor polyneuropathy of axonal or mixed axonal and demyelinating type in 97 (70%). Cryptogenic polyneuropathy is a slowly progressive sensorimotor nerve lesion of mainly axonal type. Men are more often affected than women. Most patients have a minor or moderate severe polyneuropathy.
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Li AH, Rosenquist R, Forestier E, Lindh J, Roos G. Detailed clonality analysis of relapsing precursor B acute lymphoblastic leukemia: implications for minimal residual disease detection. Leuk Res 2001; 25:1033-45. [PMID: 11684274 DOI: 10.1016/s0145-2126(01)00072-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Genetic instability has important implications for detection of minimal residual disease (MRD) when the target is a clonal genetic marker revealed at diagnosis. A successful MRD detection approach requires a stable marker and for lymphoid leukemias clonal rearrangements of immunoglobulin (Ig) and T cell receptor (TCR) genes are commonly used. In the present study, Ig heavy chain (IgH) and TCR (gamma and delta) genes were studied in 18 consecutive, relapsing precursor-B ALL patients. At least one clonal rearrangement was found in all cases at presentation (IgH 94%, TCRgamma 39% and TCRdelta 28%). An altered rearrangement pattern between diagnosis and relapse was demonstrated in 14 patients (78%). At least one stable molecular target was found in 13 out of 18 cases (72%). Clonal differences between diagnostic and relapse samples were explained by: (1) loss of original rearrangements; (2) V(H) to DJ(H) joining; (3) V(H) gene replacement; (4) appearance of new rearrangements. In two cases with apparently new IgH gene rearrangements at relapse extended sequencing of the diagnostic samples revealed minor clonal rearrangements identical to the relapse clones. Interestingly, one patient displayed instability on both the IgH and TCR gene loci, whereas a stable Igkappa rearrangement was found at presentation and relapse. These data show that clonal diversity is common in precursor-B ALL and strongly suggest that MRD detection should include multiple gene targets to minimize false-negative samples. Even so, five of our 18 relapse cases (28%) lacked stable clonal markers and should have been unsuitable for MRD detection.
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Botero-Kleiven S, Fernández V, Lindh J, Richter-Dahlfors A, von Euler A, Wahlgren M. Receptor-mediated endocytosis in an apicomplexan parasite (Toxoplasma gondii). Exp Parasitol 2001; 98:134-44. [PMID: 11527436 DOI: 10.1006/expr.2001.4624] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Endocytosis mechanisms are poorly known in apicomplexan parasites. Here, we show that extracellular tachyzoites of Toxoplasma gondii bind and internalize heparin-like sulfated glycans in a specific, saturable manner. Discrete binding of the glycan occurs at the anterior third of the tachyzoite, where it is rapidly concentrated inside single tubulo vesicular compartments that become multiple with time. The compound is held for several hours intracellularly with no apparent exocytosis or acidification. Incubation in the continuous presence of fluorescein isothiocyanate-conjugated heparin enhances the binding and internalization of this ligand by live tachyzoites. Two tachyzoite surface polypeptides exhibit strong binding and specificity for heparin, making them candidate receptors. Uptake of fluid-phase endocytic tracers occurs via nonspecific pinocytosis in the same region of the parasite cell, but with much lower efficiency. These observations show that extracellular tachyzoites can acquire molecules through both receptor-specific and fluid-phase endocytic mechanisms. Understanding the physiological relevance of these processes for the extracellular and intracellular stages of T. gondii may bring about direct targeting of the parasite by drug delivery into the tachyzoites.
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Kuratli S, Hemphill A, Lindh J, Smith DF, Connolly B. Secretion of the novel Trichinella protein TSJ5 by T. spiralis and T. pseudospiralis muscle larvae. Mol Biochem Parasitol 2001; 115:199-208. [PMID: 11420106 DOI: 10.1016/s0166-6851(01)00287-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The Trichinella tsJ5 gene is preferentially expressed in muscle larvae of Trichinella spiralis and encodes a novel protein. Previous observations have shown tsJ5 to be expressed at higher levels in encapsulating species than in non-encapsulating species and down-regulation of gene expression in T. pseudospiralis to be correlated with a lower protein abundance in the muscle larva of this species. In the present study we have determined the full-length cDNA sequence of the tsJ5 homologue in T. pseudospiralis (tpJ5). Antigens recognised by an anti-J5 antibody are found on the cuticular surface of both T. spiralis and T. pseudospiralis muscle larvae, as well as in the body wall muscle. We show that both the TSJ5 and TPJ5 proteins are found in the excretory/secretory fractions collected from muscle larva cultured in vitro and that despite the absence of a typical N-terminal signal sequence, secretion of pTSJ5 is mediated through the classical ER/Golgi secretory pathway.
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Remes K, Norrback KF, Rosenquist R, Mehle C, Lindh J, Roos G. Telomere length and telomerase activity in malignant lymphomas at diagnosis and relapse. Br J Cancer 2000; 82:601-7. [PMID: 10682672 PMCID: PMC2363336 DOI: 10.1054/bjoc.1999.0970] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Telomere length maintenance, in the vast majority of cases executed by telomerase, is a prerequisite for long-term proliferation. Most malignant tumours, including lymphomas, are telomerase-positive and this activity is a potential target for future therapeutic interventions since inhibition of telomerase has been shown to result in telomere shortening and cell death in vitro. One prerequisite for the suitability of anti-telomerase drugs in treating cancer is that tumours exhibit shortened telomeres compared to telomerase-positive stem cells. A scenario is envisioned where the tumour burden is reduced using conventional therapy whereafter remaining tumour cells are treated with telomerase inhibitors. In evaluating the realism of such an approach it is essential to know the effects on telomere status by traditional therapeutic regimens. We have studied the telomere lengths in 47 diagnostic lymphomas and a significant telomere shortening was observed compared to benign lymphoid tissues. In addition, telomere length and telomerase activity were studied in consecutive samples from patients with relapsing non-Hodgkin's lymphomas. Shortened, unchanged and elongated telomere lengths were observed in the relapse samples. The telomere length alterations found in the relapsing lymphomas appeared to be independent of telomerase and rather represented clonal selection random at the telomere length level. These data indicate that anti-telomerase therapy would be suitable in only a fraction of malignant lymphomas.
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Li AH, Rosenquist R, Forestier E, Holmberg D, Lindh J, Löfvenberg E, Roos G. Clonal rearrangements in childhood and adult precursor B acute lymphoblastic leukemia: a comparative polymerase chain reaction study using multiple sets of primers. Eur J Haematol 1999; 63:211-8. [PMID: 10530408 DOI: 10.1111/j.1600-0609.1999.tb01880.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ig heavy chain (IgH) and T-cell receptor (TCR) gene rearrangements were investigated by polymerase chain reaction (PCR) amplification of diagnostic tumour samples from 91 patients (57 children and 34 adults, with cut-off at age 16) with precursor B acute lymphoblastic leukemia (ALL). Using primers directed to the framework regions (FR) 1, 2 and 3 of the IgH gene, clonal IgH rearrangements were observed in 82, 58 and 58%, respectively, whereas clonality was presented in 45 and 27% using primers hybridising to the TCR delta and gamma genes. A combination of all five primer sets used resulted in 96% positive cases (children 100%, adults 88%). The frequency of clonal IgH rearrangements correlated to patient age with a significantly lower fraction of positive cases in the adult group. The concomitant usage of more than one V(H) family gene was similar for childhood and adult ALL, and an over-representation of V(H)6 rearrangements was found in childhood ALL. Twenty-five out of 91 cases (27%) displayed an oligoclonal pattern for either IgH or TCR gene rearrangements (children 37%, adults 12%). A comparative analysis of samples from different compartments was performed in 23 patients, and differences between two or three compartments were observed in seven cases. Unexpectedly large, clonally appearing PCR products of 540-715 bp were found in three leukemias and sequence analysis verified their clonal nature. In summary, using multiple sets of primers clonal rearrangements of IgH and TCR genes can be detected in a very high frequency, including previously neglected large size PCR products. A common heterogeneity was demonstrated in different compartments reflecting ongoing clonal evolution, which can make detection of minimal residual disease (MRD) in ALL troublesome. Therefore, we suggest that a minimum of three targets should be used to minimise false-negative results.
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Rosenquist R, Thunberg U, Li AH, Forestier E, Lönnerholm G, Lindh J, Sundström C, Sällström J, Holmberg D, Roos G. Clonal evolution as judged by immunoglobulin heavy chain gene rearrangements in relapsing precursor-B acute lymphoblastic leukemia. Eur J Haematol 1999; 63:171-9. [PMID: 10485272 DOI: 10.1111/j.1600-0609.1999.tb01765.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oligoclonality and ongoing clonal evolution are common features in patients with precursor-B (pre-B) acute lymphoblastic leukemia (ALL), as judged by immunoglobulin heavy chain (IgH) gene rearrangement analysis. These features are considered to be results of secondary rearrangements after malignant transformation or emergence of new tumor clones. In the present study we analyzed the IgH gene rearrangement status in 18 cases with relapsing pre-B ALL using variable heavy chain (V(H)) gene family specific polymerase chain reaction (PCR) amplification and single stranded conformation polymorphism (SSCP) analysis. Clonal IgH rearrangements were displayed in all leukemias but one, and altered rearrangement patterns occurred in five cases (29%), which were selected for detailed nucleotide sequence analysis. In one case, multiple subclones at diagnosis were suggested to be derived from a progenitor clone through joining of different V(H) germline gene segments to a pre-existing D-J(H) complex (V(H) to D-J(H) joining). Evidence for V(H) gene replacement with identical N-sequences at the V(H)-D junction and a common D-J(H) region was observed in one case. Diversification at the V(H)-D junction consisting of heterogeneous N-sequences were observed in one case. This molecular modification of the V(H)-D region could fit a hypothesized "open-and-shut" mechanism. Nevertheless, despite these ongoing events at least one IgH rearrangement remained unchanged throughout the disease in most patients, indicating that the immunoglobulin heavy chain locus can be a suitable marker for detection of minimal residual disease (MRD).
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