Production et charactérisation des anticorps monoclonaux contre le cytomegalovirus

L'objectif de ce projet a été la production des anticorps monoclonaux dirigés contre le cytomegalovirus (CMV) pour fin d'utilisation potentielle en diagnostic et/ou l'utilisation comme outil pour etudier les aspects fondamentaux du CMV. Des anticorps monoclonaux ont été obtenus par fusion de lymphocytes de souris (immunisées par quatre injections intrapéritonéales de 500 mg à intervale de deux semaines) et des cellules de mylome de souris (NSO) maintenues en culture exponentielle. Le dépistage des clones sécréteurs a été effectué par ELISA et immunofluorescence (IF). Les hybridomes intéressants ont été clonés par dilution limite puis congelés dans l'azote liquide et injectés par voie intrapéritonéale chez des souris (BALB/c), traitées avec une injection intrapéritonéale de 0.7 ml de pristane (2,4,10,14-Tetramethylpentadecane) dix jours auparavant, pour la production de liquide ascitique. Parmi les clones sélectionnés, un seul s'est révélé d'un grand intérêt. Le clone CLB-1 s'est révélé d'une grande reactivité et d'une grande spécificité contre le CMV. Le liquide ascitique produit par les cellules monoclonales CLB-1 a été testé et les aspects suivants des réactions entre le CLB-1 et le CMV ont été vérifiés: (a) Reactivité et spécificité de l'anticorps contre le CMV. Pour étudier ce phénomène, l'anticorps monoclonal (CLB-1) a été testé par IF (en dilution de 1:100) contre des cellules fibroblastiques infectées par le CMV (AD169) ou par l'Herpès simplex type-1 ou type-2. Les résultats ont montré une réaction positive avec les cellules infectées par le CMV (AD169) et négative avec les cellules non-infectées ou infectées par l'Herpès sipmlex type-1 ou type-2. (b) La capacité de cet anticorps (CLB-1) pour la detection des isolées cliniques de CMV a été vérifié. L'anticorps monoclonal a détecté toutes les isolées cliniques trouvés positives au CMV. (c) Pour étudier la cinétique de la synthèse de la protéine contre lequel l'anticorps monoclonal est dirigé, le CLB-1 a été testé en IF avec des cellules fibroblastiques infectées avec le CMV à des temps différents après l'infection. Les résultats ont montré une réaction positive entre 72 et 96 heures après 11 infection prouvant ainsi que la protéine contre laquelle CLB-1 est dirigé est une protéine tardive. (d) La capacité neutralisante de 11 anticorps a été vérifiée et il a été prouvé que ce derniér neutralise le virus à une dilution de 1:100 comparativement au sérum humain ayant une capacité neutralisante à une dilution de 1:5. (e) Finalement le test d'immunodiffusion double sur gel d1 agarose a montré que 1'anticorps monoclonal CLB-1 est de type IgGl. Plusieurs essais ont été effectués afin de déterminer le poids moléculaire de la (les) protéine(s) contre laquelle 11 anticorps CLB-1 est dirigé. Par immunoblotting, il nous a été impossible d1 identifier cette (ces) protéine (s). La raison probable est la destruction ou la modification de 11 épitope dans le processus de préparation de 11 antigene. Il a été mentionné que la majorité des anticorps monoclonaux ne précipitent pas les antigene contre lesquels ils sont dirigés (Carter and Ter Meulen, In advances in virus research. 1984, 29: 95-130). En conclusion nous avons produit un anticorps monoclonal contre le CMV, cet anticorps peut nous aider pour les diagnostic et probablement pour le traitement de 1'infection virale de CMV.Fusions of spleen cells obtained from mice immunized with human cytomegalovirus (CMV) and a mouse myeloma cell line were performed. One monoclonal antibody, CLB-1 was obtained from the four fusions performed. The following aspects of the reaction of the monocolona1 antibody CLB-1, with CMV were investigated: (a) The reactivity and specificity of CLB-1 with CMV; (b) the ability of the CLB-1 monoclonal antibody to detect clinical isolates of CMV; (c ) the kinetics of synthesis of the protein against which the CLB-1 monoclonal antibody reacts ; (d) the ability of the CLB-1 to neutralize CMV; and (e) some characteristics of this monoclonal antibody. The data obtained showed that the CLB-1 monoclonal antibody detected cells infected with CMV A D16 9 , the strain which was used as the immunizing antigen. The CLB-1 antibody showed a high degree cf specificity for the CMV as it did not react with the herpes simplex type-1, herpes simplex type-2 infected cells nor with uninfected human fibroblasts. From the kinetic experiments, the data obtained showed that this monoclonal antibody was directed against a late protein(s) that appeared between 72h and 96h post-infection. The CLB-1 antibody neutralized the virus completely at a dilution of 1:100 of an acitis fluid preparation. Using the double immunodiffusion method, the CLB-1 antibody was found to belong to the IgGl sub-class of immunoglobulinsMontréal Trigonix inc. 201

Entrepreneurship attributes that help to develop photography graduates as entrepreneurs / Nur Akma Halili ... [et. al]

This study focuses on the involvement of photography graduates in commercial photography entrepreneurship or photography business. In the 10th Malaysian Plan, one of the government strategies has put target to transform Malaysia into high income nation. It is therefore, education through higher learning institutions particular young graduates is the targeted group to fulfill this strategy. This includes UiTM particularly photography graduates who have good potential to involve themselves in various photographic businesses. The objectives of this study are to investigate how many photography graduates who have involve in photographic businesses; and to analyse why the numbers of graduates are not interested in photographic entrepreneurship. The two main methods will be employed in this study: questionnaire and interview in obtaining relevant data and information to selected graduates, lecturers as well as graduates who have succeed in photography entrepreneurship. The significance of this the study will help to improve the current photography curriculum as well as to become guidelines for lecturers and current students to involve in photography entrepreneurship. Directly, it will help to government aspiration to become as a high-income nation

Semantic intelligence in a seaport context

This research work proposes the framework for seaport partners to interact on a semantic level and scope related with jurisdictions/ecosystems and regions to share knowledge among partners. New steps towards dealing with the traditional common sense for managing or governing the seaport are required for assisting the new generation of managers and port authorities. Sematic intelligence answers dilemmas of complex realities and alignments of strategies such as which strategic position may have the seaport facing the growing number of international networks and international treaties. In management and computational sciences, semantic intelligence has been discussed mostly from technological perspectives; however, a higher thinking intelligence for managing and govern the seaport surplus the classical intelligence approach found in literature

Arabidopsis thaliana cells: a model to evaluate the virulence of Pectobacterium carotovorum.

Pectobacterium carotovorum are economically important plant pathogens that cause plant soft rot. These enterobacteria display high diversity world-wide. Their pathogenesis depends on production and secretion of virulence factors such as plant cell wall-degrading enzymes, type III effectors, a necrosis-inducing protein, and a secreted virulence factor from Xanthomonas spp., which are tightly regulated by quorum sensing. Pectobacterium carotovorum also present pathogen-associated molecular patterns that could participate in their pathogenicity. In this study, by using suspension cells of Arabidopsis thaliana, we correlate plant cell death and pectate lyase activities during coinfection with different P. carotovorum strains. When comparing soft rot symptoms induced on potato slices with pectate lyase activities and plant cell death observed during coculture with Arabidopsis thaliana cells, the order of strain virulence was found to be the same. Therefore, Arabidopsis thaliana cells could be an alternative tool to evaluate rapidly and efficiently the virulence of different P. carotovorum strains

Exceptionally high work density of a ferroelectric dynamic organic crystal around room temperature

Dynamic organic crystals are rapidly gaining traction as a new class of smart materials for energy conversion, however, they are only capable of very small strokes (<12%) and most of them operate through energetically cost-prohibitive processes at high temperatures. We report on the exceptional performance of an organic actuating material with exceedingly large stroke that can reversibly convert energy into work around room temperature. When transitioning at 295–305 K on heating and at 265–275 K on cooling the ferroelectric crystals of guanidinium nitrate exert a linear stroke of 51%, the highest value observed with a reversible operation of an organic single crystal actuator. Their maximum force density is higher than electric cylinders, ceramic piezoactuators, and electrostatic actuators, and their work capacity is close to that of thermal actuators. This work demonstrates the hitherto untapped potential of ionic organic crystals for applications such as light-weight capacitors, dielectrics, ferroelectric tunnel junctions, and thermistors

Beyond the pandemic : COVID-19 pandemic changed the face of life

Funding Information: This work was supported by the Swedish Research Council Vetenskapsr?det (VR grant 2016?05885). Funding Information: Acknowledgments: H.R. El-Seedi is very grateful to the Swedish Research links grant VR 2016– 05885 and the Department of Molecular Biosciences, Wenner-Grens Institute, Stockholm University, Sweden, for the financial support. Publisher Copyright: © 2021 by the au-thors. Licensee MDPI, Basel, Switzerland.The COVID-19 pandemic is a serious challenge for societies around the globe as entire populations have fallen victim to the infectious spread and have taken up social distancing. In many countries, people have had to self-isolate and to be confined to their homes for several weeks to months to prevent the spread of the virus. Social distancing measures have had both negative and positive impacts on various aspects of economies, lifestyles, education, transportation, food supply, health, social life, and mental wellbeing. On other hands, due to reduced population movements and the decline in human activities, gas emissions decreased and the ozone layer improved; this had a positive impact on Earth’s weather and environment. Overall, the COVID-19 pandemic has negative effects on human activities and positive impacts on nature. This study discusses the impact of the COVID-19 pandemic on different life aspects including the economy, social life, health, education, and the environment.publishersversionPeer reviewe

Signal transducer and activator of transcription 3 (Stat3) suppresses stat1/interferon signaling pathway and inflammation in senescent preadipocytes

© 2021 by the authors. Licensee MDPI, Basel, Switzerland. Obesity promotes premature aging and dysfunction of white adipose tissue (WAT) through the accumulation of cellular senescence. The senescent cells burden in WAT has been linked to inflammation, insulin‐resistance (IR), and type 2 diabetes (T2D). There is limited knowledge about molecular mechanisms that sustain inflammation in obese states. Here, we describe a robust and physiologically relevant in vitro system to trigger senescence in mouse 3T3‐L1 preadipocytes. By employing transcriptomics analyses, we discovered up‐regulation of key pro‐inflammatory molecules and activation of interferon/signal transducer and activator of transcription (STAT)1/3 signaling in senescent preadipocytes, and expression of downstream targets was induced in epididymal WAT of obese mice, and obese human adipose tissue. To test the relevance of STAT1/3 signaling to preadipocyte senescence, we used Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated protein 9 (CRISPR/Cas9) technology to delete STAT1/3 and discovered that STAT1 promoted growth arrest and cooperated with cyclic Guanosine Monophosphate‐Adenosine Monophosphate (GMP‐AMP) synthase‐stimulator of interferon genes (cGAS‐STING) to drive the expression of interferon β (IFNβ), C‐X‐C motif chemokine ligand 10 (CXCL10), and interferon signaling‐related genes. In contrast, we discovered that STAT3 was a negative regulator of STAT1/cGAS‐STING signaling—it suppressed senescence and inflammation. These data provide insights into how STAT1/STAT3 signaling coordinates senescence and inflammation through functional interactions with the cGAS/STING pathway

A lightweight neural network with multiscale feature enhancement for liver CT segmentation

Segmentation of abdominal Computed Tomography (CT) scan is essential for analyzing, diagnosing, and treating visceral organ diseases (e.g., hepatocellular carcinoma). This paper proposes a novel neural network (Res-PAC-UNet) that employs a fixed-width residual UNet backbone and Pyramid Atrous Convolutions, providing a low disk utilization method for precise liver CT segmentation. The proposed network is trained on medical segmentation decathlon dataset using a modified surface loss function. Additionally, we evaluate its quantitative and qualitative performance; the Res16-PAC-UNet achieves a Dice coefficient of 0.950 ± 0.019 with less than half a million parameters. Alternatively, the Res32-PAC-UNet obtains a Dice coefficient of 0.958 ± 0.015 with an acceptable parameter count of approximately 1.2 million.This publication was made possible by NPRP-11S-1219-170106 from the Qatar National Research Fund (a member of Qatar Foundation). The findings herein reflect the work, and are solely the responsibility of the authors

Integrated supply–demand energy management for optimal design of off-grid hybrid renewable energy systems for residential electrification in arid climates

The growing research interest in hybrid renewable energy systems (HRESs) has been regarded as a natural and yet critical response to address the challenge of rural electrification. Based on a Bibliometric analysis performed by authors, it was concluded that most studies simply adopted supply-side management techniques to perform the design optimization of such a renewable energy system. To further advance those studies, this paper presents a novel approach by integrating demand-supply management (DSM) with particle swarm optimization and applying it to optimally design an off-grid hybrid PV-solar-diesel-battery system for the electrification of residential buildings in arid environments, using a typical dwelling in Adrar, Algeria, as a case study. The proposed HRES is first modelled by an in-house MATLAB code based on a multi-agent system concept and then optimized by minimizing the total net present cost (TNPC), subject to reliability level and renewable energy penetration. After validation against the HOMER software, further techno-economic analyses including sensitivity study are undertaken, considering different battery technologies. By integrating the proposed DSM, the results have shown the following improvements: with RF = 100%, the energy demand and TNPC are reduced by 7% and 18%, respectively, compared to the case of using solely supply-side management. It is found that PV-Li-ion represents the best configuration, with TNPC of $23,427 and cost of energy (COE) of 0.23$/kWh. However, with lower RF values, the following reductions are achieved: energy consumption (19%) and fuel consumption or CO 2 emission (57%), respectively. In contrast, the RF is raised from 15% (without DSM) to 63% (with DSM). It is clear that the optimal configuration consists of wind-diesel, with COE of 0.21 $/kWh, smaller than that obtained with a stand-alone diesel generator system. The outcomes of this work can provide valuable insights into the successful design and deployment of HRES in Algeria and surrounding regions