218 research outputs found

    Transmission of Human Immunodeficiency Virus I Drug Resistance - a Case Report. What are the Clinical Implications?

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    The success of first-line antiretroviral therapy can be challenged by the acquisition of primary drug resistance. Here we report a case where baseline genotypic resistance testing detected resistance conferring nucleoside/nucleotide reverse transcriptase inhibitor (NRTI)-associated mutations, but no primary mutations for protease inhibitor (PI). Subsequent PI-based HAART with boosted saquinavir led to virological treatment success with persistently undetectable viral load. After treatment simplification from saquinavir to an atazanavir based PI-therapy and no change in backbone therapy rapid virological breakthrough occurred. Retrospective analysis displayed preexisting gag cleavage site mutations which may have reduced the genetic barrier in a clinical relevant manner in combination with the already existing NRTI resistance mutations. Alternatively, this effect could be explained with a different antiviral potency for the respective PIs used

    Cancer risk in HIV-infected individuals on HAART is largely attributed to oncogenic infections and state of immunocompetence

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    <p>Abstract</p> <p>Objectives</p> <p>To estimate the cancer risk of HIV-infected patients in the HAART era with respect to a general reference population and to determine risk factors for malignancy.</p> <p>Methods</p> <p>Long term (1996-2009) cancer incidence of the Bonn single centre HIV cohort was compared to the incidence of the reference population of Saarland using standardized incidence ratios (SIR). Poisson regression analysis was used to identify predictors of cancer risk.</p> <p>Results</p> <p>1,476 patients entered the cohort, enabling 8,772 person years of observation. 121 tumours in 114 patients, 7 in-situ and 114 invasive cancers, were identified. Malignancies associated with infectious agents such as Kaposi sarcoma (SIRs: male: 5,683; female: 277), non-Hodgkin lymphoma (SIRs male: 35; female: 18), anal cancer (SIRs male: 88; female: 115) as well a cervical carcinoma (SIR female: 4) and Hodgkin's disease (SIR male: 39) and liver cancer (SIR male: 18) were substantially more frequent in HIV-infected patients than in the general population (p < 0.001, each), whereas all other types of cancer were not increased. Poisson regression identified HAART (incidence rate ratio IRR (95% CI): 0.28 (0.19-0.41), p < 0.001), CD4 count (IRR per 100 cells/μl increase: 0.66 (0.57-0.76), p < 0.001), hepatitis B (IRR: 2.15 (1.10-4.20), p = 0.046) and age (IRR per 10 year increase: 1.23 (1.03 - 1.46), p = 0.023) as independent predictors for the occurrence of any type of cancer.</p> <p>Conclusions</p> <p>HAART and preserved CD4 cells preferentially reduce the risk of malignancies associated with oncogenic infections.</p

    Dissociation by steroids of eosinophilic inflammation from airway hyperresponsiveness in murine airways

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    BACKGROUND: The link between eosinophils and the development of airway hyperresponsiveness (AHR) in asthma is still controversial. This question was assessed in a murine model of asthma in which we performed a dose ranging study to establish whether the dose of steroid needed to inhibit the eosinophil infiltration correlated with that needed to block AHR. METHODS: The sensitised BALB/c mice were dosed with vehicle or dexamethasone (0.01–3 mg/kg) 2 hours before and 6 hours after each challenge (once daily for 6 days) and 2 hours before AHR determination by whole-body plethysmography. At 30 minutes after the AHR to aerosolised methacholine the mice were lavaged and differential white cell counts were determined. Challenging with antigen caused a significant increase in eosinophils in the bronchoalveolar lavage (BAL) fluid and lung tissue, and increased AHR. RESULTS: Dexamethasone reduced BAL and lung tissue eosinophilia (ED(50 )values of 0.06 and 0.08 mg/kg, respectively), whereas a higher dose was needed to block AHR (ED(50 )of 0.32 mg/kg at 3 mg/ml methacholine. Dissociation was observed between the dose of steroid needed to affect AHR in comparison with eosinophilia and suggests that AHR is not a direct consequence of eosinophilia. CONCLUSION: This novel pharmacological approach has revealed a clear dissociation between eosinophilia and AHR by using steroids that are the mainstay of asthma therapy. These data suggest that eosinophilia is not associated with AHR and questions the rationale that many pharmaceutical companies are adopting in developing low-molecular-mass compounds that target eosinophil activation/recruitment for the treatment of asthma

    Mineral Preservatives in the Wood of Stradivari and Guarneri

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    Following the futile efforts of generations to reach the high standard of excellence achieved by the luthiers in Cremona, Italy, by variations of design and plate tuning, current interest is being focused on differences in material properties. The long-standing question whether the wood of Stradivari and Guarneri were treated with wood preservative materials could be answered only by the examination of wood specimens from the precious antique instruments. In a recent communication (Nature, 2006), we reported about the degradation of the wood polymers in instruments of Stradivari and Guarneri, which could be explained only by chemical manipulations, possibly by preservatives. The aim of the current work was to identify the minerals from the small samples of the maple wood which were available to us from the antique instruments. The ashes of wood from one violin and one cello by Stradivari, two violins by Guarneri, one viola by H. Jay, one violin by Gand-Bernardel were analyzed and compared with a variety of commercial tone woods. The methods of analysis were the following: back-scattered electron imaging, X-ray fluorescence maps for individual elements, wave-length dispersive spectroscopy, energy dispersive X-ray spectroscopy and quantitative microprobe analysis. All four Cremonese instruments showed the unmistakable signs of chemical treatments in the form of chemicals which are not present in natural woods, such as BaSO4, CaF2, borate, and ZrSiO4. In addition to these, there were also changes in the common wood minerals. Statistical evaluation of 12 minerals by discriminant analysis revealed: a. a difference among all four Cremona instruments, b. the difference of the Cremonese instruments from the French and English antiques, and c. only the Cremonese instruments differed from all commercial woods. These findings may provide the answer why all attempts to recreate the Stradivarius from natural wood have failed. There are many obvious implications with regard to how the green tone wood should be treated, which chould lead to changes in the practice of violin-making. This research should inspire others to analyze more antique violins for their chemical contents

    Reduced Lung Function in a Chronic Asthma Model Is Associated with Prolonged Inflammation, but Independent of Peribronchial Fibrosis

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    In asthma, mechanisms contributing to chronicity remain to be determined. Recent models of sensitisation with prolonged airway allergen challenges reproduce typical features of chronic asthma. However, the interplay between inflammation, structural changes and lung function is poorly understood. This study was performed to delineate functional, structural and immunological airway changes after cessation of long term challenges to elucidate factors contributing to the development of prolonged lung function changes.Mice sensitised systemically were consecutively challenged intranasally with ovalbumin for two or eight weeks. After the end of challenges, lung function, airway inflammation, features of airway remodelling, local T-cell cytokines and systemic ovalbumin-specific antibodies were monitored. Long term challenges resulted in airway hyperresponsiveness lasting 2 weeks and reduced baseline lung function for 6 weeks after their cessation. In contrast, these changes resolved within one week after short term challenges. Prolonged transforming growth factor beta (TGF-beta)1 production and marked peribronchial fibrosis were only induced by long term challenges. Importantly, fibrosis became apparent only after the onset of lung function changes and outlasted them. Further, long term challenges led to prolonged and intense airway inflammation with marked lymphocytosis, but moderate eosinophilia, sustained IL-5 production and ovalbumin-specific IgG2a antibodies, the latter suggesting a Th1 component to the immune response. In contrast, following short term challenges airway inflammation was dominated by eosinophils and associated with a strong, but transient IL-13 response.Prolonged lung function changes after long term allergen challenges seem to develop and resolve independently of the persistent peribronchial fibrosis. They are more closely associated with intense airway inflammation, marked lymphocytosis, prolonged IL-5 and TGF-beta1 production in the airways and a Th1 immune response

    Characterization of a Novel Binding Protein for Fortilin/TCTP — Component of a Defense Mechanism against Viral Infection in Penaeus monodon

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    The Fortilin (also known as TCTP) in Penaeus monodon (PmFortilin) and Fortilin Binding Protein 1 (FBP1) have recently been shown to interact and to offer protection against the widespread White Spot Syndrome Virus infection. However, the mechanism is yet unknown. We investigated this interaction in detail by a number of in silico and in vitro analyses, including prediction of a binding site between PmFortilin/FBP1 and docking simulations. The basis of the modeling analyses was well-conserved PmFortilin orthologs, containing a Ca2+-binding domain at residues 76–110 representing a section of the helical domain, the translationally controlled tumor protein signature 1 and 2 (TCTP_1, TCTP_2) at residues 45–55 and 123–145, respectively. We found the pairs Cys59 and Cys76 formed a disulfide bond in the C-terminus of FBP1, which is a common structural feature in many exported proteins and the “x–G–K–K” pattern of the amidation site at the end of the C-terminus. This coincided with our previous work, where we found the “x–P–P–x” patterns of an antiviral peptide also to be located in the C-terminus of FBP1. The combined bioinformatics and in vitro results indicate that FBP1 is a transmembrane protein and FBP1 interact with N-terminal region of PmFortilin

    Selective sigma-2 ligands preferentially bind to pancreatic adenocarcinomas: applications in diagnostic imaging and therapy

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    <p>Abstract</p> <p>Background</p> <p>Resistance to modern adjuvant treatment is in part due to the failure of programmed cell death. Therefore the molecules that execute the apoptotic program are potential targets for the development of anti-cancer therapeutics. The sigma-2 receptor has been found to be over-expressed in some types of malignant tumors, and, recently, small molecule ligands to the sigma-2 receptor were found to induce cancer cell apoptosis.</p> <p>Results</p> <p>The sigma-2 receptor was expressed at high levels in both human and murine pancreas cancer cell lines, with minimal or limited expression in normal tissues, including: brain, kidney, liver, lung, pancreas and spleen. Micro-PET imaging was used to demonstrate that the sigma-2 receptor was preferentially expressed in tumor as opposed to normal tissues in pancreas tumor allograft-bearing mice. Two structurally distinct sigma-2 receptor ligands, SV119 and WC26, were found to induce apoptosis to mice and human pancreatic cancer cells <it>in vitro </it>and <it>in vivo</it>. Sigma-2 receptor ligands induced apoptosis in a dose dependent fashion in all pancreatic cell lines tested. At the highest dose tested (10 μM), all sigma-2 receptor ligands induced 10–20% apoptosis in all pancreatic cancer cell lines tested (p < 0.05). In pancreas tumor allograft-bearing mice, a single bolus dose of WC26 caused approximately 50% apoptosis in the tumor compared to no appreciable apoptosis in tumor-bearing, vehicle-injected control animals (p < 0.0001). WC26 significantly slowed tumor growth after a 5 day treatment compared to vehicle-injected control animals (p < 0.0001) and blood chemistry panels suggested that there is minimal peripheral toxicity.</p> <p>Conclusion</p> <p>We demonstrate a novel therapeutic strategy that induces a significant increase in pancreas cancer cell death. This strategy highlights a new potential target for the treatment of pancreas cancer, which has little in the way of effective treatments.</p

    Securing accumulation by restoration – exploring spectacular corporate conservation, coal mining and biodiversity compensation in the German Rhineland

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    German energy giant and coal mine operator RWE makes two products: cheap electricity and ‘pretty new landscapes’. These ‘pretty new landscapes’ are biodiversity offsets to compensate for the destruction of the ancient Hambacher Forest for the world’s largest opencast lignite coal mine in the German Rhineland. Drawing on in-depth fieldwork including participant observation and interviews in and around the mine and its offset sites, this paper explores the relationship between coal mining, spectacularisation of conservation, the ecotourism–extraction nexus and accumulation by restoration. I illustrate the historic and contemporary importance of restoration activities to the accumulation process and explore the recent engagement of mine operator RWE in the provision of restored nature (in the form of ‘eco-points’), which constitute new business opportunities. The significance of RWE’s biodiversity work for accumulation by restoration lies not only in its profit opportunities but its productive power: the legitimation of coal mining and the making of new, ordered ‘ecologies of repair’. This productive power operates through the mobilising function of RWE’s offsetting work, which forms the foundation for corporate partnerships and alliances with conservation groups and volunteers. These lend legitimacy to RWE’s ‘repair work’ and form the basis for the ecotourism–extraction nexus by turning the mine and its offsets into ‘extractive attractions’ for visitors and ‘nature lovers’. Its power further manifests in the way it captures imaginations through novel imaginaries and narratives of sustainable coal mining, supposedly creating not only a ‘better nature’ but a ‘better future’. Positioning offsetting as social technology of governance, I explore RWE’s spectacular performance of sustainability and the ontological flattening to facilitate claims of commensurability and ‘offsettability’ of nature. These are integral to the ecotourism–extraction nexus and grounded in the belief in the human/corporate ability to recreate nature, a fascination with huge earth-shifting machinery and a commitment to high-modernist ideologies of control

    An Alternate STAT6-Independent Pathway Promotes Eosinophil Influx into Blood during Allergic Airway Inflammation

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    Enhanced eosinophil responses have critical roles in the development of allergic diseases. IL-5 regulates the maturation, migration and survival of eosinophils, and IL-5 and eotaxins mediate the trafficking and activation of eosinophils in inflamed tissues. CD4⁺ Th2 cells are the main producers of IL-5 and other cells such as NK also release this cytokine. Although multiple signalling pathways may be involved, STAT6 critically regulates the differentiation and cytokine production of Th2 cells and the expression of eotaxins. Nevertheless, the mechanisms that mediate different parts of the eosinophilic inflammatory process in different tissues in allergic airway diseases remain unclear. Furthermore, the mechanisms at play may vary depending on the context of inflammation and microenvironment of the involved tissues. We employed a model of allergic airway disease in wild type and STAT6-deficient mice to explore the roles of STAT6 and IL-5 in the development of eosinophilic inflammation in this context. Quantitative PCR and ELISA were used to examine IL-5, eotaxins levels in serum and lungs. Eosinophils in lung, peripheral blood and bone marrow were characterized by morphological properties. CD4⁺ T cell and NK cells were identified by flow cytometry. Antibodies were used to deplete CD4⁺ and NK cells. We showed that STAT6 is indispensible for eosinophilic lung inflammation and the induction of eotaxin-1 and -2 during allergic airway inflammation. In the absence of these chemokines eosinophils are not attracted into lung and accumulate in peripheral blood. We also demonstrate the existence of an alternate STAT6-independent pathway of IL-5 production by CD4⁺ and NK cells that mediates the development of eosinophils in bone marrow and their subsequent movement into the circulation
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