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991.
Van der Meeren A Gremy O Renault D Miroux A Bruel S Griffiths N Tourdes F 《Journal of radiation research》2012,53(2):184-194
The physico-chemical form in which plutonium enters the body influences the lung distribution and the transfer rate from lungs to blood. In the present study, we evaluated the early lung damage and macrophage activation after pulmonary contamination of plutonium of various preparation modes which produce different solubility and distribution patterns. Whatever the solubility properties of the contaminant, macrophages represent a major retention compartment in lungs, with 42 to 67% of the activity from broncho-alveolar lavages being associated with macrophages 14 days post-contamination. Lung changes were observed 2 and 6 weeks post-contamination, showing inflammatory lesions and accumulation of activated macrophages (CD68 positive) in plutonium-contaminated rats, although no increased proliferation of pneumocytes II (TTF-1 positive cells) was found. In addition, acid phosphatase activity in macrophages from contaminated rats was enhanced 2 weeks post-contamination as compared to sham groups, as well as inflammatory mediator levels (TNF-α, MCP-1, MIP-2 and CINC-1) in macrophage culture supernatants. Correlating with the decrease in activity remaining in macrophages after plutonium contamination, inflammatory mediator production returned to basal levels 6 weeks post-exposure. The production of chemokines by macrophages was evaluated after contamination with Pu of increasing solubility. No correlation was found between the solubility properties of Pu and the activation level of macrophages. In summary, our data indicate that, despite the higher solubility of plutonium citrate or nitrate as compared to preformed colloids or oxides, macrophages remain the main lung target after plutonium contamination and may participate in the early pulmonary damage. 相似文献
992.
993.
Analysis of engineered nanomaterials in complex matrices (environment and biota): general considerations and conceptual case studies 总被引:1,自引:0,他引:1
von der Kammer F Ferguson PL Holden PA Masion A Rogers KR Klaine SJ Koelmans AA Horne N Unrine JM 《Environmental toxicology and chemistry / SETAC》2012,31(1):32-49
Advances in the study of the environmental fate, transport, and ecotoxicological effects of engineered nanomaterials (ENMs) have been hampered by a lack of adequate techniques for the detection and quantification of ENMs at environmentally relevant concentrations in complex media. Analysis of ENMs differs from traditional chemical analysis because both chemical and physical forms must be considered. Because ENMs are present as colloidal systems, their physicochemical properties are dependent on their surroundings. Therefore, the simple act of trying to isolate, observe, and quantify ENMs may change their physicochemical properties, making analysis extremely susceptible to artifacts. Many analytical techniques applied in materials science and other chemical/biological/physical disciplines may be applied to ENM analysis as well; however, environmental and biological studies may require that methods be adapted to work at low concentrations in complex matrices. The most pressing research needs are the development of techniques for extraction, cleanup, separation, and sample storage that introduce minimal artifacts to increase the speed, sensitivity, and specificity of analytical techniques, as well as the development of techniques that can differentiate between abundant, naturally occurring particles, and manufactured nanoparticles. 相似文献
994.
Dale L. Bailey Henryk Barthel Bettina Beuthin-Baumann Thomas Beyer Sotirios Bisdas Ronald Boellaard Johannes Czernin Alexander Drzezga Ulrike Ernemann Christiane Franzius Brigitte Gückel Rupert Handgretinger Markus Hartenbach Dirk Hellwig Helen Nadel Stephan G. Nekolla Thomas Pfluger Bernd J. Pichler Harald H. Quick Osama Sabri Bernhard Sattler Jürgen Schäfer Fritz Schick Barry A. Siegel Heinz P. Schlemmer Nina F. Schwenzer Jörg van den Hoff Patrick Veit-Haibach Hans F. Wehrl 《Molecular imaging and biology》2014,16(3):295-310
This workshop was held a year after the initial positron emission tomography/magnetic resonance (PET/MR) workshop in Tübingen, which was recently reported in this journal. The discussions at the 2013 workshop, however, differed substantially from those of the initial workshop, attesting to the progress of combined PET/MR as an innovative imaging modality. Discussions were focused on the search for truly novel, unique clinical and research applications as well as technical issues such as reliable and accurate approaches for attenuation and scatter correction of PET emission data. The workshop provided hands-on experience with PET and MR imaging. In addition, structured and moderated open discussion sessions, including six dialogue boards and two roundtable discussions, provided input from current and future PET/MR imaging users. This summary provides a snapshot of the current achievements and challenges for PET/MR. 相似文献
995.
Philipp Wohlfarth Roman Ullrich Thomas Staudinger Andja Bojic Oliver Robak Alexander Hermann Barbara Lubsczyk Nina Worel Valentin Fuhrmann Maria Schoder Martin Funovics Werner Rabitsch Paul Knoebl Klaus Laczika Gottfried J Locker Wolfgang R Sperr Peter Schellongowski Arbeitsgruppe für h?mato-onkologische Intensivmedizin der ?sterreichischen Gesellschaft für Internistische und Allgemeine Intensivmedizin und Notfallmedizin 《Critical care (London, England)》2014,18(1)
Introduction
Acute respiratory failure (ARF) is the main reason for intensive care unit (ICU) admissions in patients with hematologic malignancies (HMs). We report the first series of adult patients with ARF and HMs treated with extracorporeal membrane oxygenation (ECMO).Methods
This is a retrospective cohort study of 14 patients with HMs (aggressive non-Hodgkin lymphoma (NHL) n = 5; highly aggressive NHL, that is acute lymphoblastic leukemia or Burkitt lymphoma, n = 5; Hodgkin lymphoma, n = 2; acute myeloid leukemia, n = 1; multiple myeloma, n = 1) receiving ECMO support because of ARF (all data as medians and interquartile ranges; age, 32 years (22 to 51 years); simplified acute physiology score II (SAPS II): 51 (42 to 65)). Etiology of ARF was pneumonia (n = 10), thoracic manifestation of NHL (n = 2), sepsis of nonpulmonary origin (n = 1), and transfusion-related acute lung injury (n = 1). Diagnosis of HM was established during ECMO in four patients, and five first received (immuno-) chemotherapy on ECMO.Results
Before ECMO, the PaO2/FiO2 ratio was 60 (53 to 65), (3.3 to 3.7). Three patients received venoarterial ECMO because of acute circulatory failure in addition to ARF; all other patients received venovenous ECMO. All patients needed vasopressors, and five needed hemofiltration. Thrombocytopenia occurred in all patients (lowest platelet count was 20 (11 to 21) G/L). Five major bleeding events were noted. ECMO duration was 8.5 (4 to 16) days. ICU and hospital survival was 50%. All survivors were alive at follow-up (36 (10 to 58) months); five patients were in complete remission, one in partial remission, and one had relapsed.Conclusions
ECMO therapy is feasible in selected patients with HMs and ARF and can be associated with long-term disease-free survival. 相似文献996.
Separation of younger red cells with improved survival in vivo: An approach to chronic transfusion therapy
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Sergio Piomelli Carol Seaman Joan Reibman Alex Tytun Joseph Graziano Nina Tabachnik Laurence Corash 《Proceedings of the National Academy of Sciences of the United States of America》1978,75(7):3474-3478
Transfusion of donor blood containing predominantly younger red cells with prolonged survival in vivo could significantly reduce the iron overload of patients requiring chronic transfusion. Age-dependent separation of red cells can be obtained by buoyant density centrifugation on isotonic solutions of arabino-galactane. By this technique, rabbit red cells were separated on a single layer of arabino-galactane and the appropriate fraction, after being labeled with (51)Cr, was reinfused into the donor. The survival in vivo was calculated by a mathematical model which corrects for both (51)Cr elution and random loss. There was a significant difference in survival in vivo between the light young red cells and the heavy old red cells. The potential survival in vivo of the 50% lightest red cells was 56 days, compared to 28 days for the heaviest red cells. Arabino-galactane appeared to be devoid of acute toxicity and of strong antigenicity and it did not appear to adhere to the red cell stroma. These data extrapolated to humans indicate that it may be feasible and advantageous to use red cells fractionated by this technique for transfusion. The 50% lightest human red cells can be expected to have a mean survival of 88 days, compared with 60 days for unfractionated blood. Transfusion of young red cells could significantly reduce the iron overload for patients requiring chronic transfusion, by avoiding infusion of the oldest red cells, which contribute equally to iron overload yet offer only transient survival in vivo. 相似文献
997.
Lei Zhang Holger Erfle Nathalie Harder Jürgen Beneke Nina Beil Ruben Bulkescher Karl Rohr Michael Keese 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2016,30(3):281-295
Purpose
Understanding of the mechanisms of vascular smooth muscle cells (VSMCs) phenotypic regulation is critically important to identify novel candidates for future therapeutic intervention. While HTS approaches have recently been used to identify novel regulators in many cell lines, such as cancer cells and hematopoietic stem cells, no studies have so far systematically investigated the effect of gene inactivation on VSMCs with respect to cell survival and growth response.Methods and Results
257 out of 2000 genes tested resulted in an inhibition of cell proliferation in HaoSMCs. After pathway analysis, 38 significant genes were selected for further study. 23 genes were confirmed to inhibit proliferation, and 13 genes found to induce apoptosis in the synthetic phenotype. 11 genes led to an aberrant nuclear phenotype indicating a central role in cell mitosis. 4 genes affected the cell migration in synthetic HaoSMCs. Using computational biological network analysis, 11 genes were identified to have an indirect or direct interaction with the Osteopontin pathway. For 10 of those genes, levels of proteins downstream of the Osteopontin pathway were found to be down-regulated, using RNAi methodology.Conclusions
A phenotypic high-throughput siRNA screen could be applied to identify genes relevant for the cell biology of HaoSMCs. Novel genes were identified which play a role in proliferation, apoptosis, mitosis and migration of HaoSMCs. These may represent potential drug candidates in the future.998.
999.
1000.
Martina Huemer Daniel R. Carvalho Jaime M. Brum Özlem Ünal Turgay Coskun James D. Weisfeld-Adams Nina L. Schrager Sabine Scholl-Bürgi Andrea Schlune Markus G. Donner Martin Hersberger Claudio Gemperle Brunhilde Riesner Hanno Ulmer Johannes Häberle Daniela Karall 《Journal of inherited metabolic disease》2016,39(3):331-340