29 research outputs found
Chitosan–Starch–Keratin composites: Improving thermo-mechanical and degradation properties through chemical modification
The lysozyme test shows an improved in the degradability rate, the weight loss of the films at 21 days is reduced from 73 % for chitosan-starch matrix up to 16 % for the composites with 5wt% of quill; but all films show a biodegradable character depending on keratin type and chemical modification. The outstanding properties related to the addition of treated keratin materials show that these natural composites are a remarkable alternative to potentiat-ing chitosan–starch films with sustainable featuresChitosan–starch polymers are reinforced with different keratin materials obtained from chicken feather. Keratin materials are treated with sodium hydroxide; the modified surfaces are rougher in comparison with untreated surfaces, observed by Scanning Electron Microscopy. The results obtained by Differential Scanning Calorimetry show an increase in the endothermic peak related to water evaporation of the films from 92 °C (matrix) up to 102–114 °C (reinforced composites). Glass transition temperature increases from 126 °C in the polymer matrix up to 170–200 °C for the composites. Additionally, the storage modulus in the composites is enhanced up to 1614 % for the composites with modified ground quill, 2522 % for composites with modified long fiber and 3206 % for the composites with modified short fiber. The lysozyme test shows an improved in the degradability rate, the weight loss of the films at 21 days is reduced from 73 % for chitosan-starch matrix up to 16 % for the composites with 5wt% of quill; but all films show a biodegradable character depending on keratin type and chemical modification. The outstanding properties related to the addition of treated keratin materials show that these natural composites are a remarkable alternative to potentiat-ing chitosan–starch films with sustainable featuresUniversidad Autónoma del Estado de México Tecnológico Nacional de México, Instituto Tecnológico de Querétaro Universidad Nacional Autónoma de México Tecnológico Nacional de México, Instituto Tecnológico de Celaya Universidad Autónoma de Cd. Juáre
CUORE and CUORE-0 experiments
Neutrino oscillation experiments proved that neutrinos have mass and this enhanced the interest in neutrinoless double-beta decay (0vßß). The observation of this very rare hypothetical decay would prove the leptonic number violation and would give us indications about neutrinos mass hierarchy and absolute mass scale. CUORE (Cryogenic Underground Observatory for Rare Events) is an array of 988 crystals of TeO2, for a total sensitive mass of 741 kg. Its goal is the observation of 0vßß of 130Te. The crystals, placed into the a dilution cryostat, are operated as bolometers at a temperature close to 10 mK. CUORE commissioning phase has been concluded recently in Gran Sasso National Laboratory, Italy, and data taking is expected to start in spring 2017. If target background rate is reached (0.01counts/day/keV/kg), the sensibility of CUORE will be, in five years of data taking, T1/21026years (1? CL). In order to test the quality of materials and optimize the construction procedures, the collaboration realized CUORE-0, that took data from spring of 2013 to summer 2015. Here, after a brief description of CUORE, I report its commissioning status and CUORE-0 results
Phylogenetic evidence for the invasion of a commercialized European Phasmarhabditis hermaphrodita lineage into North America and New Zealand
Biological control (biocontrol) as a component of pest management strategies reduces reliance on synthetic chemicals, and seemingly offers a natural approach that minimizes environmental impact. However, introducing a new organism to new environments as a classical biocontrol agent can have broad and unanticipated biodiversity effects and conservation consequences. Nematodes are currently used in a variety of commercial biocontrol applications, including the use of Phasmarhabditis hermaphrodita as an agent targeting pest slug and snail species. This species was originally discovered in Germany, and is generally thought to have European origins. P. hermaphrodita is sold under the trade name Nemaslug®, and is available only in European markets. However, this nematode species was discovered in New Zealand and the western United States, though its specific origins remained unclear. In this study, we analyzed 45 nematode strains representing eight different Phasmarhabditis species, collected from nine countries around the world. A segment of nematode mitochondrial DNA (mtDNA) was sequenced and subjected to phylogenetic analyses. Our mtDNA phylogenies were overall consistent with previous analyses based on nuclear ribosomal RNA (rRNA) loci. The recently discovered P. hermaphrodita strains in New Zealand and the United States had mtDNA haplotypes nearly identical to that of Nemaslug®, and these were placed together in an intraspecific monophyletic clade with high support in maximum likelihood and Bayesian analyses. We also examined bacteria that co-cultured with the nematode strains isolated in Oregon, USA, by analyzing 16S rRNA sequences. Eight different bacterial genera were found to associate with these nematodes, though Moraxella osloensis, the bacteria species used in the Nemaslug® formulation, was not detected. This study provided evidence that nematodes deriving from the Nemaslug® biocontrol product have invaded countries where its use is prohibited by regulatory agencies and not commercially available
MicroRNA-146 Inhibits Thrombin-Induced NF-jB Activation and Subsequent Inflammatory Responses in Human Retinal Endothelial Cells
PURPOSE. Nuclear factor-jB (NF-jB), a key regulator of immune and inflammatory responses, plays important roles in diabetes-induced microvascular complications including diabetic retinopathy (DR). Thrombin activates NF-jB through protease-activated receptor (PAR)-1, a member of the G-protein-coupled receptor (GPCR) superfamily, and contributes to DR. The current study is to uncover the roles of microRNA (miRNA) in thrombin-induced NF-jB activation and retinal endothelial functions. METHODS. Target prediction was performed using the TargetScan algorithm. Predicted target was experimentally validated by luciferase reporter assays. Human retinal endothelial cells (HRECs) were transfected with miRNA mimics or antimiRs and treated with thrombin. Expression levels of miR-146 and related protein-coding genes were analyzed by quantitative (q)RT-PCR. Functional changes of HRECs were analyzed by leukocyte adhesion assays. RESULTS. We identified that caspase-recruitment domain (CARD)-containing protein 10 (CARD10), an essential scaffold/adaptor protein of GPCR-mediated NF-jB activation pathway, is a direct target of miR-146. Thrombin treatment resulted in NF-jB-dependent upregulation of miR-146 in HRECs; while transfection of miR-146 mimics resulted in significant downregulation of CARD10 and prevented thrombin-induced NF-jB activation, suggest that a negative feedback regulation of miR-146 on thrombin-induced NF-jB through targeting CARD10. Furthermore, overexpression of miR-146 prevented thrombin-induced increased leukocyte adhesion to HRECs. CONCLUSIONS. We uncovered a novel negative feedback regulatory mechanism on thrombininduced GPCR-mediated NF-jB activation by miR-146. In combination with the negative feedback regulation of miR-146 on the IL-1R/toll-like receptor (TLR)-mediated NF-jB activation in RECs that we reported previously, our results underscore a pivotal, negative regulatory role of miR-146 on multiple NF-jB activation pathways and related inflammatory processes in DR. Keywords: microRNA, diabetic retinopathy, retinal endothelial cells, NF-kB activation, thrombin D iabetic retinopathy (DR) is the leading cause of blindness in people between ages of 25 and 74 in the industrialized world. 1 Nearly all individuals who have had type I diabetes for more than 15 years develop DR. Approximately 50% to 80% of type II diabetic patients also develop retinopathy after 20 years of diabetes. 2 Although progress has been made, there is still no preventive treatment. MicroRNAs (miRNAs) are small, noncoding RNAs, and represent a newly recognized, important level of geneexpression regulation. 3,4 However, the roles of miRNAs in DR are still largely unknown. Previously, to identify miRNAs involved in DR, we performed miRNA-expression profiling and established miRNA transcriptomes of the retina and retinal endothelial cells (RECs) of normal control and streptozotocin (STZ)-induced diabetic rats 3 months after the onset of diabetes. 5 Among inflammation-related miRNAs, we showed that miR-146 was upregulated in RECs of diabetic rats
Use of the HRM diversity assay as part of a multi-assay algorithm for HIV incidence determination.
<p>Panel A shows one example of a multi-assay algorithm developed for HIV incidence determination. In this algorithm, samples from HIV-infected individuals are first tested using the BED-CEIA assay, using a high assay cutoff to indicate non-recent HIV infection (BED screen). Samples that are below the BED screen cutoff (BED recent samples) are then tested using a second serologic assay, such as one based on antibody avidity (avidity screen). Samples that are below the cutoff for the second serologic assay are considered to be “serologic recent” samples. Samples with low CD4 cell count test results are then excluded as non-recent (note that CD4 cell count test results are usually obtained for all HIV-infected individuals at the time of sample collection). Finally, samples that are not excluded based on CD4 cell count are tested using a viral load assay, and samples with low viral loads are excluded as non-recent. The remaining samples are characterized as recent for the purpose of estimating HIV incidence. Panel B shows an alternative multi-assay algorithm that incorporates the HRM diversity assay. In this algorithm, samples that are characterized as serologic recent based on two assays (BED screen and an avidity screen) are tested with a multi-region HRM diversity assay. Samples that have a high HRM score in at least one of the regions tested are excluded as non-recent. Samples that fail to amplify in all regions tested are also excluded as non-recent, based on the assumption that they have low viral loads; this could be confirmed with a viral load assay. Samples that have low HRM scores in all regions tested are characterized as recent for the purpose of estimating HIV incidence.</p