399 research outputs found
Dynamics of cell population structure in liver biopsy of the patients with chronic hepatitis viral infection
The cell population analysis of liver biopsies from the patients with both chronic hepatitis, chronic viral hepatitis C (HCV) and chronic viral hepatitis B (HBV) included the comparative evaluation of the specific part of non-parenchymal elements, analysis of the liver plates and sinusoids areas, the cell population of liver plates and sinusoids, the caryometric description of different types of cells. The essential difference of similar quantitative indexes in the biopsy specimens of patients with HCV and НВV was revealed and discussed. In total, the quantitative analysis of cell population structure in liver biopsies during the course of chronic hepatitis, especially in the case of defective biopsies, could be used for diagnostics and prognoses by expert evaluation
Somalie
Daraasaad la sameeyey 1966 oo ku saabsan sidii ay ku suurtaggeli lahayd warshadaynta dalka Soomaaliya iyo diraasaad dhaqaale oo halkaas lagu qoondaynayo mashaariic.Studio sulle possibilità di industrializzazione della Somalia effettuato nel 1966 e studio economico dei progetti in essere.A study on the possibilities of industrialization of Somalia carried out in 1966 and an economic study of the projects in place.Link:http://aei.pitt.edu/34949/1/A1100.pd
Key parameters design for online battery electrochemical impedance tracker
International audienceNew applications in transport and energy storage require the use of Lithium-ion batteries. Advanced battery management systems including electrochemical impedance measurement are studied for the determination of the state of the battery, the prediction of the autonomy, the failure and security management. Taking into account constraints of cost and simplicity, we propose to use the existing electronics of current control and we evaluate the effect of the electronics design on the performance of a frequency evolutionary estimation of the electrochemical impedance. This recursive method relies on a wideband active approach and provides both an accurate estimate of the impedance in the frequency area and a tracking of its temporal variations. Benefits are the limitation of the data memory required and the amount of operations that can be completely carried out by a target such as a microcontroller. We propose a methodology to design the key parameters of electronics in function of the frequency band of interest and the desired accuracy. We highlighted that electronics of conventional BMS can host this tracking algorithm, with analog to digital converters of 10 bits or more, having an analog stage to adapt their dynamics, and that microcontrollers can be enough powerful to perform calculations, both in terms of number of operations and speed of execution. This design strategy has been applied to define a prototyping environment for a BMS based on an ARM microcontroller which is expected to provide the tracking impedance of a battery every 250 ms with less than 0,5 % of error
Process analytical utility of Raman spectroscopy for cell therapy manufacturing
Please click Additional Files below to see the full abstract
A Multi-Parameter, High-Content, High-Throughput Screening Platform to Identify Natural Compounds that Modulate Insulin and Pdx1 Expression
Diabetes is a devastating disease that is ultimately caused by the malfunction or loss of insulin-producing pancreatic beta-cells. Drugs capable of inducing the development of new beta-cells or improving the function or survival of existing beta-cells could conceivably cure this disease. We report a novel high-throughput screening platform that exploits multi-parameter high-content analysis to determine the effect of compounds on beta-cell survival, as well as the promoter activity of two key beta-cell genes, insulin and pdx1. Dispersed human pancreatic islets and MIN6 beta-cells were infected with a dual reporter lentivirus containing both eGFP driven by the insulin promoter and mRFP driven by the pdx1 promoter. B-score statistical transformation was used to correct systemic row and column biases. Using this approach and 5 replicate screens, we identified 7 extracts that reproducibly changed insulin and/or pdx1 promoter activity from a library of 1319 marine invertebrate extracts. The ability of compounds purified from these extracts to significantly modulate insulin mRNA levels was confirmed with real-time PCR. Insulin secretion was analyzed by RIA. Follow-up studies focused on two lead compounds, one that stimulates insulin gene expression and one that inhibits insulin gene expression. Thus, we demonstrate that multi-parameter, high-content screening can identify novel regulators of beta-cell gene expression, such as bivittoside D. This work represents an important step towards the development of drugs to increase insulin expression in diabetes and during in vitro differentiation of beta-cell replacements
Hypoxia-inducible factor-1alpha is a critical mediator of hypoxia induced apoptosis in cardiac H9c2 and kidney epithelial HK-2 cells
<p>Abstract</p> <p>Background</p> <p>Hypoxia inducible factor-1 (HIF-1) is a transcription factor that functions to maintain cellular homeostasis in response to hypoxia. There is evidence that HIF-1 can also trigger apoptosis, possibly when cellular responses are inadequate to meet energy demands under hypoxic conditions.</p> <p>Methods</p> <p>Cardiac derived H9c2 and renal tubular epithelial HK-2 cells expressing either the wild type oxygen regulated subunit of HIF-1 (pcDNA3-Hif-1α) or a dominant negative version that lacked both DNA binding and transactivation domains (pcDNA3-DN-Hif-1α), were maintained in culture and exposed to hypoxia. An RNA interference approach was also employed to selectively knockdown expression of Hif-1α. Apoptosis was analyzed in both H9c2 and HK-2 cells by Hoechst and TUNEL staining, caspase 3 activity assays and activation of pro-apoptotic Bcl2 family member Bax.</p> <p>Results</p> <p>Overexpression of pcDNA3-DN-Hif-1α led to a significant reduction in hypoxia -induced apoptosis (17 ± 2%, <it>P </it>< 0.01) in H9c2 cells compared to both control-transfected and wild type Hif-1α transfected cells. Moreover, selective ablation of HIF-1α protein expression by RNA interference in H9c2 cells led to 55% reduction of caspase 3 activity and 46% reduction in the number of apoptotic cells as determined by Hoechst 33258 staining, after hypoxia. Finally, upregulation of the pro-apoptotic protein, Bax, was found in H9c2 cells overexpressing full-length pcDNA3-HA-HIF-1α exposed to hypoxia. In HK-2 cells overexpression of wild-type Hif-1α led to a two-fold increase in Hif-1α levels during hypoxia. This resulted in a 3.4-fold increase in apoptotic cells and a concomitant increase in caspase 3 activity during hypoxia when compared to vector transfected control cells. HIF-1α also induced upregulation of Bax in HK-2 cells. In addition, introduction of dominant negative Hif-1α constructs in both H9c2 and HK-2 -cells led to decreased active Bax expression.</p> <p>Conclusion</p> <p>These data demonstrate that HIF-1α is an important component of the apoptotic signaling machinery in the two cell types.</p
Genome-wide scan identifies CDH13 as a novel susceptibility locus contributing to blood pressure determination in two European populations
Hypertension is a complex disease that affects a large proportion of adult population. Although approximately half of the inter-individual variance in blood pressure (BP) level is heritable, identification of genes responsible for its regulation has remained challenging. Genome-wide association study (GWAS) is a novel approach to search for genetic variants contributing to complex diseases. We conducted GWAS for three BP traits [systolic and diastolic blood pressure (SBP and DBP); hypertension (HYP)] in the Kooperative Gesundheitsforschung in der Region Augsburg (KORA) S3 cohort (n = 1644) recruited from general population in Southern Germany. GWAS with 395 912 single nucleotide polymorphisms (SNPs) identified an association between BP traits and a common variant rs11646213 (T/A) upstream of the CDH13 gene at 16q23.3. The initial associations with HYP and DBP were confirmed in two other European population-based cohorts: KORA S4 (Germans) and HYPEST (Estonians). The associations between rs11646213 and three BP traits were replicated in combined analyses (dominant model: DBP, P = 5.55 × 10–5, effect –1.40 mmHg; SBP, P = 0.007, effect –1.56 mmHg; HYP, P = 5.30 × 10−8, OR = 0.67). Carriers of the minor allele A had a decreased risk of hypertension. A non-significant trend for association was also detected with severe family based hypertension in the BRIGHT sample (British). The novel susceptibility locus, CDH13, encodes for an adhesion glycoprotein T-cadherin, a regulator of vascular wall remodeling and angiogenesis. Its function is compatible with the BP biology and may improve the understanding of the pathogenesis of hypertension
Nanoscale surface topography reshapes neuronal growth in culture
International audienceNeurons are sensitive to topographical cues provided either by in vivo or in vitro environments on the micrometric scale. We have explored the role of randomly distributed silicon nanopillars on primary hippocampal neurite elongation and axonal differentiation. We observed that neurons adhere on the upper part of nanopillars with a typical distance between adhesion points of about 500 nm. These neurons produce fewer neurites, elongate faster, and differentiate an axon earlier than those grown on flat silicon surfaces. Moreover, when confronted with a differential surface topography, neurons specify an axon preferentially on nanopillars. As a whole, these results highlight the influence of the physical environment in many aspects of neuronal growth
Template-based Fault Injection Analysis of Block Ciphers
We present the first template-based fault injection analysis of FPGA-based block cipher implementations. While template attacks have been a popular form of side-channel analysis in the cryptographic literature, the use of templates in the context of fault attacks has not yet been explored to the best of our knowledge. Our approach involves two phases. The first phase is a profiling phase where we build templates of the fault behavior of a cryptographic device for different secret key segments under different fault injection intensities. This is followed by a matching phase where we match the observed fault behavior of an identical but black-box device with the pre-built templates to retrieve the secret key. We present a generic treatment of our template-based fault attack approach for SPN block ciphers, and illustrate the same with case studies on a Xilinx Spartan-6 FPGA-based implementation of AES-128
Phosphorylation of p65(RelA) on Ser547 by ATM Represses NF-κB-Dependent Transcription of Specific Genes after Genotoxic Stress
The NF-κB pathway is involved in immune and inflammation responses, proliferation, differentiation and cell death or survival. It is activated by many external stimuli including genotoxic stress. DNA double-strand breaks activate NF-κB in an ATM-dependent manner. In this manuscript, a direct interaction between p65(RelA) and the N-terminal extremity of ATM is reported. We also report that only one of the five potential ATM-(S/T)Q target sites present in p65, namely Ser547, is specifically phosphorylated by ATM in vitro. A comparative transcriptomic analysis performed in HEK-293 cells expressing either wild-type HA-p65 or a non-phosphorylatable mutant HA-p65S547A identified several differentially transcribed genes after an etoposide treatment (e.g. IL8, A20, SELE). The transcription of these genes is increased in cells expressing the mutant. Substitution of Ser547 to alanine does not affect p65 binding abilities on the κB site of the IL8 promoter but reduces p65 interaction with HDAC1. Cells expressing p65S547A have a higher level of histone H3 acetylated on Lys9 at the IL8 promoter, which is in agreement with the higher gene induction observed. These results indicate that ATM regulates a sub-set of NF-κB dependent genes after a genotoxic stress by direct phosphorylation of p65
- …