779 research outputs found

    Actual versus Optimal Fisheries Policies: An Evaluation of the Cod Fishing Policies of Denmark, Iceland and Norway

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    Many ocean fisheries are subject to a fundamental economic problem generally referred to as the common property problem. The common property problem manifests itself as excessive fishing fleets and fishing effort, depressed fish stocks and little or no profitability of the fishing activity, irrespective of the richness of the underlying marine resources. European fisheries represent some of the most dramatic examples of the common property problem. This paper employs simple empirical models and recently developed mathe-matical techniques to find optimal feed-back policies to examine the economic efficiency of three European fisheries, namely the Danish, Icelandic and Nor-wegian cod fisheries. The optimal harvesting policies for each of these fisheries are calculated. Comparing these optimal policies with actual harvests provides a measure of the relative efficiency in these three cod fisheries. The comparison confirms that the cod harvesting policies of these three coun-tries have been hugely inefficient in the past. Moreover, it appears that the inef-ficiency has been increasing over time. Only, during the last few years of our data are there indications that this downward trend may have been halted. This comparative improvement, slight as it is, may reflect the impact of a more re-strictive fisheries policy since the early 1990s

    Actual versus Optimal Fisheries Policies: An Evaluation of the Cod Fishing Policies of Denmark, Iceland and Norway

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    Many ocean fisheries are subject to a fundamental economic problem generally referred to as the common property problem. The common property problem manifests itself as excessive fishing fleets and fishing effort, depressed fish stocks and little or no profitability of the fishing activity, irrespective of the richness of the underlying marine resources. European fisheries represent some of the most dramatic examples of the common property problem. This paper employs simple empirical models and recently developed mathe-matical techniques to find optimal feed-back policies to examine the economic efficiency of three European fisheries, namely the Danish, Icelandic and Nor-wegian cod fisheries. The optimal harvesting policies for each of these fisheries are calculated. Comparing these optimal policies with actual harvests provides a measure of the relative efficiency in these three cod fisheries. The comparison confirms that the cod harvesting policies of these three coun-tries have been hugely inefficient in the past. Moreover, it appears that the inef-ficiency has been increasing over time. Only, during the last few years of our data are there indications that this downward trend may have been halted. This comparative improvement, slight as it is, may reflect the impact of a more re-strictive fisheries policy since the early 1990s.

    A study of the association of HLA DR, DQ, and complement C4 alleles with systemic lupus erythematosus in Iceland

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    To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldOBJECTIVE: To perform an exploratory analysis of the relative contribution of single MHC genes to the pathogenesis of systemic lupus erythematosus (SLE) in a homogenous white population. METHODS: MHC class II alleles and C4 allotypes were determined in 64 SLE patients and in ethnically matched controls. HLA-DR and DQ typing was performed by polymerase chain reaction amplification with sequence specific primers. C4 allotypes were determined by agarose gel electrophoresis. RESULTS: The frequency of C4A*Q0 was significantly higher in patients than in controls (46.9% v 25.3%, p = 0.002). HLA-DRB1, DQA1, and DQB1 alleles in the whole group of SLE patients were not significantly different from those of controls. On the other hand increase in DRB1*03 was observed in the group of patients with C4A*Q0, as compared with patients with other C4A allotypes (p = 0.047). There was no significant correlation between severe and mild disease, as judged by the SLEDAI, and HLADR, DQ alleles and comparing the patients with C4A*Q0 with those with other C4A allotypes there was no significant difference regarding clinical manifestations. CONCLUSION: The results are consistent with the argument that C4A deficiency contributes independently to susceptibility and the pathogenesis of SLE. C4A*Q0 in SLE patients in Iceland shows weaker linkage disequilibrium with DR3 genes than reported in most other white populations and emphasises the role of ethnicity

    APC loss in breast cancer leads to doxorubicin resistance via STAT3 activation

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    Resistance to chemotherapy is one of the leading causes of death from breast cancer. We recently established that loss of Adenomatous Polyposis Coli (APC) in the Mouse Mammary Tumor Virus – Polyoma middle T (MMTV-PyMT) transgenic mouse model results in resistance to cisplatin or doxorubicin-induced apoptosis. Herein, we aim to establish the mechanism that is responsible for APC-mediated chemotherapeutic resistance. Our data demonstrate that MMTV-PyMT;ApcMin/+ cells have increased signal transducer and activator of transcription 3 (STAT3) activation. STAT3 can be constitutively activated in breast cancer, maintains the tumor initiating cell (TIC) population, and upregulates multidrug resistance protein 1 (MDR1). The activation of STAT3 in the MMTV-PyMT;ApcMin/+ model is independent of interleukin 6 (IL-6); however, enhanced EGFR expression in the MMTV-PyMT;ApcMin/+ cells may be responsible for the increased STAT3 activation. Inhibiting STAT3 with a small molecule inhibitor A69 in combination with doxorubicin, but not cisplatin, restores drug sensitivity. A69 also decreases doxorubicin enhanced MDR1 gene expression and the TIC population enhanced by loss of APC. In summary, these results have revealed the molecular mechanisms of APC loss in breast cancer that can guide future treatment plans to counteract chemotherapeutic resistance

    Coalescent-based genome analyses resolve the early branches of the euarchontoglires

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    Despite numerous large-scale phylogenomic studies, certain parts of the mammalian tree are extraordinarily difficult to resolve. We used the coding regions from 19 completely sequenced genomes to study the relationships within the super-clade Euarchontoglires (Primates, Rodentia, Lagomorpha, Dermoptera and Scandentia) because the placement of Scandentia within this clade is controversial. The difficulty in resolving this issue is due to the short time spans between the early divergences of Euarchontoglires, which may cause incongruent gene trees. The conflict in the data can be depicted by network analyses and the contentious relationships are best reconstructed by coalescent-based analyses. This method is expected to be superior to analyses of concatenated data in reconstructing a species tree from numerous gene trees. The total concatenated dataset used to study the relationships in this group comprises 5,875 protein-coding genes (9,799,170 nucleotides) from all orders except Dermoptera (flying lemurs). Reconstruction of the species tree from 1,006 gene trees using coalescent models placed Scandentia as sister group to the primates, which is in agreement with maximum likelihood analyses of concatenated nucleotide sequence data. Additionally, both analytical approaches favoured the Tarsier to be sister taxon to Anthropoidea, thus belonging to the Haplorrhine clade. When divergence times are short such as in radiations over periods of a few million years, even genome scale analyses struggle to resolve phylogenetic relationships. On these short branches processes such as incomplete lineage sorting and possibly hybridization occur and make it preferable to base phylogenomic analyses on coalescent methods

    Comparative chromosome painting discloses homologous Segments in distantly related mammals

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    Comparative chromosome painting, termed ZOO-FISH, using DNA libraries from flow sorted human chromosomes 1,16,17 and X, and mouse chromosome 11 discloses the presence of syntenic groups in distantly related mammalian Orders ranging from primates (Homo sapiens), rodents (Mus musculus), even-toed ungulates (Muntiacus muntjak vaginalis and Muntiacus reevesi) and whales (Balaenoptera physalus). These mammalian Orders have evolved separately for 55-80 million years (Myr). We conclude that ZOO-FISH can be used to generate comparative chromosome maps of a large number of mammalian species

    Plain language summary of the TRANSFORM study primary analysis results:liso-cell as a second treatment regimen for large B-cell lymphoma following failure of the first treatment regimen

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    What is this summary about?People diagnosed with a disease called large B-cell lymphoma (LBCL) may experience return, or early relapse, of their disease within the first year after receiving and responding to their first (first-line) treatment regimen. Others may have primary refractory disease, meaning that the disease either did not respond to first-line treatment at all or only responded for a very brief period. Second (second-line) treatment includes immunotherapy followed by high-dose chemotherapy and ASCT, which has the potential to cure LBCL. However, if the disease does not respond to immunotherapy, people cannot receive ASCT, and less than 30% of people are cured.Therefore, new second-line treatment options are required, such as CAR T cell therapy, which uses a person's own genetically engineered lymphocytes, also called T cells, to fight their lymphoma. In this article, we summarize the key results of the phase 3 TRANSFORM clinical study that tested if liso-cel, a CAR T cell treatment, can safely and effectively be used as a second-line treatment for people with early relapsed or primary refractory (relapsed/refractory) LBCL.A total of 184 adults with relapsed/refractory LBCL who were able to receive ASCT were randomly treated with either liso-cel or standard of care (SOC) as second-line treatment. SOC included immunochemotherapy followed by high-dose chemotherapy and ASCT.What were the key takeaways?Almost all (97%) people in the liso-cel group completed treatment, whereas 53% of people in the SOC group did not complete treatment, mostly due to their disease not responding or relapsing, and therefore they were not able to receive ASCT. People who received liso-cel as a second-line treatment lived longer without the occurrence of an unfavorable medical event or worsening of the disease and had a better response to treatment than those who received SOC as second-line treatment. People who received liso-cel reported side effects that researchers considered to be manageable, and that were known to occur with CAR T cell treatment.What were the main conclusions reported by the researchers?Results from the TRANSFORM study support the use of liso-cel as a more effective second-line treatment compared with SOC that is safe for people with relapsed/refractory LBCL

    Static stretching of the hamstring muscle for injury prevention in football codes: a systematic review

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    Purpose: Hamstring injuries are common among football players. There is still disagreement regarding prevention. The aim of this review is to determine whether static stretching reduces hamstring injuries in football codes. Methods: A systematic literature search was conducted on the online databases PubMed, PEDro, Cochrane, Web of Science, Bisp and Clinical Trial register. Study results were presented descriptively and the quality of the studies assessed were based on Cochrane’s ‘risk of bias’ tool. Results: The review identified 35 studies, including four analysis studies. These studies show deficiencies in the quality of study designs. Conclusion: The study protocols are varied in terms of the length of intervention and follow-up. No RCT studies are available, however, RCT studies should be conducted in the near future
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