203 research outputs found
Combination of optison with ultrasound and electroporation increases albumin and thrompoietin transgene expression whilst elongation factor promoter prolongs its duration
Hypoalbuminaemia and thrombocytopaenia are two clinical problems frequently encountered in patients with chronic liver failure or cancer following treatment with chemotherapy. The current study was designed to assess the
magnitude and duration of thrombopoietin and albumin transgene expression hoping to increase the production of
albumin and platelets. Immunocompetent and immunocompromised (nude) mice were injected intramuscularly
with plasmids expressing either human serum albumin or human thrombopoietin. The therapeutic expression cassette of the plasmids was driven by either CMV or elongation factor 1- promoters respectively. In order to achieve muscle specific expression both gene constructs included the myosin light chain enhancer. The experiment was conducted in a group of mice which were injected with the transgene plasmid either in normal saline or plasmid
followed by electroporation, ultrasound, optison and a combination of all three to increase transgene expression.
The result showed that plasmids with the CMV promoter induced the highest transgenic expression lasting for one
week whilst plasmids with the elongation factor 1-alpha promoter produced a weaker expression lasting for a longer and more stable duration of expression up to 3 months in both immunocompetent and nude mice. The combination of electroporation and ultrasound with Optison TM provided the highest transgene expression. We concluded that it would be possible to increase albumin and platelets production by an intramuscular injection of plasmids expressing human albumin and thromopoietin. A combination of electroporation and ultrasound with Optison TM can increase their expression
Effects of Two Species of VA Mycorrhizal Fungi on Drought Tolerance of Winter Wheat
Roots and soils from western Nebraska fields of native and planted grasslands, and winter wheat of varied fallow-wheat cultivation duration, were evaluated for vesicular-arbuscular (VA) mycorrhizal root infection and spore numbers and types. Increased cultivation decreased percentage mycorrhizal infection in wheat and reduced spore numbers of Glomus fasciculatus, the dominant VA mycorrhizal fungus in these soils. Spore numbers of other VA mycorrhizal fungi did not change significantly with cultivation although mean numbers of G. mosseae increased with continued wheat production. Water relations and growth were determined for greenhouse-grown non-mycorrhizal, G. fasciculatus-infected, and G. mosseae-infected wheat in wet and dry soils. Stomatal conductances were higher in mycorrhizal than in non-mycorrhizal plants in both wet and dry treatments. Stomatal closure in mycorrhizal plants occurred at lower leaf water potentials (ψ1) and after greater desiccation than in non-mycorrhizal plants, but some leaves of G. masseae-infected plants showed no stomatal response to drought and continued to transpire at ψ1 as low as -4◦1 MPa. Leaf osmotic adjustment was greater for G. fasciculatus-infected plants. Non-mycorrhizal and G. fasciculatus-infected plants had equal dry wts in both wet and dry conditions. Infection by G. fasciculatus appeared to increase wheat drought tolerance while infection by G. mosseae did not
Repeated bedside echocardiography in children with respiratory failure
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to verify the benefits and limitations of repeated bedside echocardiographic examinations in children during mechanical ventilation. For the purposes of this study, we selected the data of over a time period from 2006 to 2010.</p> <p>Methods</p> <p>A total of 235 children, average age 3.21 (SD 1.32) years were included into the study and divided into etiopathogenic groups. High-risk groups comprised: Acute lung injury and acute respiratory distress syndrome (ALI/ARDS), return of spontaneous circulation after cardiopulmonary resuscitation (ROSC), bronchopulmonary dysplasia (BPD), cardiomyopathy (CMP) and cardiopulmonary disease (CPD). Transthoracic echocardiography was carried out during mechanical ventilation. The following data were collated for statistical evaluation: right and left ventricle myocardial performance indices (RV MPI; LV MPI), left ventricle shortening fraction (SF), cardiac output (CO), and the mitral valve ratio of peak velocity of early wave (E) to the peak velocity of active wave (A) as E/A ratio. The data was processed after a period of recovery, i.e. one hour after the introduction of invasive lines (time-1) and after 72 hours of comprehensive treatment (time-2). The overall development of parameters over time was compared within groups and between groups using the distribution-free Wilcoxons and two-way ANOVA tests.</p> <p>Results</p> <p>A total of 870 echocardiographic examinations were performed. At time-1 higher average values of RV MPI (0.34, SD 0.01 vs. 0.21, SD 0.01; p < 0.001) were found in all groups compared with reference values. Left ventricular load in the high-risk groups was expressed by a higher LV MPI (0.39, SD 0.13 vs. 0.29, SD 0.02; p < 0.01) and lower E/A ratio (0.95, SD 0.36 vs. 1.36, SD 0.64; p < 0.001), SF (0.37, SD 0.11 vs. 0.47, SD 0.02; p < 0.01) and CO (1.95, SD 0.37 vs. 2.94, SD 1.03; p < 0.01). At time-2 RV MPI were lower (0.25, SD 0.02 vs. 0.34, SD 0.01; p < 0.001), but remained higher compared with reference values (0.25, SD 0.02 vs. 0.21, SD 0.01; p < 0.05). Other parameters in high-risk groups were improved, but remained insignificantly different compared with reference values.</p> <p>Conclusion</p> <p>Echocardiography complements standard monitoring of valuable information regarding cardiac load in real time. Chest excursion during mechanical ventilation does not reduce the quality of the acquired data.</p
Effects of Ferumoxides – Protamine Sulfate Labeling on Immunomodulatory Characteristics of Macrophage-like THP-1 Cells
Superparamagnetic Iron Oxide (SPIO) complexed with cationic transfection agent is used to label various mammalian cells. Labeled cells can then be utilized as an in vivo magnetic resonance imaging (MRI) probes. However, certain number of in vivo administered labeled cells may be cleared from tissues by the host's macrophages. For successful translation to routine clinical application of SPIO labeling method it is important that this mode of in vivo clearance of iron does not elicit any diverse immunological effects. The purpose of this study was to demonstrate that SPIO agent ferumoxides-protamine sulfate (FePro) incorporation into macrophages does not alter immunological properties of these cells with regard to differentiation, chemotaxis, and ability to respond to the activation stimuli and to modulate T cell response. We used THP-1 cell line as a model for studying macrophage cell type. THP-1 cells were magnetically labeled with FePro, differentiated with 100 nM of phorbol ester, 12-Myristate-13-acetate (TPA) and stimulated with 100 ng/ml of LPS. The results showed 1) FePro labeling had no effect on the changes in morphology and expression of cell surface proteins associated with TPA induced differentiation; 2) FePro labeled cells responded to LPS with slightly higher levels of NFκB pathway activation, as shown by immunobloting; TNF-α secretion and cell surface expression levels of CD54 and CD83 activation markers, under these conditions, were still comparable to the levels observed in non-labeled cells; 3) FePro labeling exhibited differential, chemokine dependent, effect on THP-1 chemotaxis with a decrease in cell directional migration to MCP-1; 4) FePro labeling did not affect the ability of THP-1 cells to down-regulate T cell expression of CD4 and CD8 and to induce T cell proliferation. Our study demonstrated that intracellular incorporation of FePro complexes does not alter overall immunological properties of THP-1 cells. The described experiments provide the model for studying the effects of in vivo clearance of iron particles via incorporation into the host's macrophages that may follow after in vivo application of any type of magnetically labeled mammalian cells. To better mimic the complex in vivo scenario, this model may be further exploited by introducing additional cellular and biological, immunologically relevant, components
Extrinsic Fluorescent Dyes as Tools for Protein Characterization
Noncovalent, extrinsic fluorescent dyes are applied in various fields of protein analysis, e.g. to characterize folding intermediates, measure surface hydrophobicity, and detect aggregation or fibrillation. The main underlying mechanisms, which explain the fluorescence properties of many extrinsic dyes, are solvent relaxation processes and (twisted) intramolecular charge transfer reactions, which are affected by the environment and by interactions of the dyes with proteins. In recent time, the use of extrinsic fluorescent dyes such as ANS, Bis-ANS, Nile Red, Thioflavin T and others has increased, because of their versatility, sensitivity and suitability for high-throughput screening. The intention of this review is to give an overview of available extrinsic dyes, explain their spectral properties, and show illustrative examples of their various applications in protein characterization
Targeting of PI3K/AKT/mTOR pathway to inhibit T cell activation and prevent graft-versus-host disease development
Producción CientíficaBackground: Graft-versus-host disease (GvHD) remains the major obstacle to successful allogeneic hematopoietic stem cell transplantation, despite of the immunosuppressive regimens administered to control T cell alloreactivity. PI3K/AKT/mTOR pathway is crucial in T cell activation and function and, therefore, represents an attractive therapeutic target to prevent GvHD development. Recently, numerous PI3K inhibitors have been developed for cancer therapy. However, few studies have explored their immunosuppressive effect. Methods: The effects of a selective PI3K inhibitor (BKM120) and a dual PI3K/mTOR inhibitor (BEZ235) on human T cell proliferation, expression of activation-related molecules, and phosphorylation of PI3K/AKT/mTOR pathway proteins were analyzed. Besides, the ability of BEZ235 to prevent GvHD development in mice was evaluated. Results: Simultaneous inhibition of PI3K and mTOR was efficient at lower concentrations than PI3K specific targeting. Importantly, BEZ235 prevented naïve T cell activation and induced tolerance of alloreactive T cells, while maintaining an adequate response against cytomegalovirus, more efficiently than BKM120. Finally, BEZ235 treatment significantly
improved the survival and decreased the GvHD development in mice. Conclusions: These results support the use of PI3K inhibitors to control T cell responses and show the potential utility of the dual PI3K/mTOR inhibitor BEZ235 in GvHD prophylaxis.Asociación Española Contra el Cáncer (Proyecto AIOA110296BLAN).Gerencia Regional de Salud de Castilla y León (Proyecto GRS 726/A13
CD14+ macrophages that accumulate in the colon of African AIDS patients express pro-inflammatory cytokines and are responsive to lipopolysaccharide
Why and how to spare the hippocampus during brain radiotherapy: the developing role of hippocampal avoidance in cranial radiotherapy
Cyclooxygenases and the cardiovascular system.
Cyclooxygenase (COX)-1 and COX-2 are centrally important enzymes within the cardiovascular system with a range of diverse, sometimes opposing, functions. Through the production of thromboxane, COX in platelets is a pro-thrombotic enzyme. By contrast, through the production of prostacyclin, COX in endothelial cells is antithrombotic and in the kidney regulates renal function and blood pressure. Drug inhibition of COX within the cardiovascular system is important for both therapeutic intervention with low dose aspirin and for the manifestation of side effects caused by nonsteroidal anti-inflammatory drugs. This review focuses on the role that COX enzymes and drugs that act on COX pathways have within the cardiovascular system and provides an in-depth resource covering COX biology and pharmacology. The review goes on to consider the role of COX in both discrete cardiovascular locations and in associated organs that contribute to cardiovascular health. We discuss the importance of, and strategies to manipulate the thromboxane: prostacyclin balance. Finally within this review the authors discuss testable COX-2-hypotheses intended to stimulate debate and facilitate future research and therapeutic opportunities within the field
- …