Plant defence peptides

Eight families of antimicrobial peptides, ranging in size from 2 to 9 kD, have been identified in plants. These are thionins, defcnsins, so-called lipid iransfer proteins, hevein- and knottin-Iike peptides, MBPJ, lb AMP, and the recently reported snakins. All of them have compact structures that are stabilized by 2-6 disulfide bridges. They are part of both permanent and inducible defense barriers. Transgenic overe.xpression of the corresponding genes leads to enhanced tolerance to pathogens, and peptide-sensitive pathogen mutants have reduced virulence

Impact du diabète sur le travail et usage des antidiabétiques oraux chez les travailleurs au Québec

Ce mémoire a deux volets. L'objectif du premier était d'évaluer l'impact du diabète de type 2 sur la productivité au travail. Les objectifs du deuxième étaient de décrire la persistance et l'observance aux traitements antidiabétiques et de déterminer les facteurs y étant associés chez des travailleurs atteints de diabète de type 2. Au premier volet, nous avons effectué une synthèse systématique des connaissances. Au deuxième, nous avons réalisé une étude de cohorte à l'aide des données administratives de la Régie de l'assurance maladie du Québec. Selon notre synthèse, le diabète a un impact négatif significatif sur la productivité au travail. Parmi les 41006 sujets de la cohorte, 81,1% prenaient leur traitement un an après son début et de ceux-ci 69,7% avaient eu en leur possession des médicaments antidiabétiques pendant au moins 80% des jours de cette première année. La persistance et l'observance aux traitements antidiabétiques sont affectées par plusieurs déterminants

Studies of the antitumor mechanism of action of dermaseptin B2, a multifunctional cationic antimicrobial peptide, reveal a partial implication of cell surface glycosaminoglycans

Dermaseptin-B2 (DRS-B2) is a multifunctional cationic antimicrobial peptide (CAP) isolated from frog skin secretion. We previously reported that DRS-B2 possesses anticancer and antiangiogenic activities in vitro and in vivo. In the present study, we evaluated the antiproliferative activity of DRS-B2 on numerous tumor cell lines, its cell internalization and studies of its molecular partners as well as their influences on its structure. Confocal microscopy using ([Alexa594]-(Cys0)-DRS-B2) shows that in sensitive human tumor cells (PC3), DRS-B2 seems to accumulate rapidly at the cytoplasmic membranes and enters the cytoplasm and the nucleus, while in less sensitive tumor cells (U87MG), DRS-B2 is found packed in vesicles at the cell membrane. Furthermore FACS analysis shows that PC3 cells viability decreases after DRS-B2 treatment while U87 MG seems to be unaffected. However, "pull down" experiments performed with total protein pools from PC3 or U87MG cells and the comparison between the antiproliferative effect of DRS-B2 and its synthetic analog containing all Damino acids suggest the absence of a stereo-selective protein receptor. Pretreatment of PC3 cells with sodium chlorate, decreases the antiproliferative activity of DRS-B2. This activity is partially restored after addition of exogenous chondroitin sulfate C (CS-C). Moreover, we demonstrate that at nanomolar concentrations CS-C potentiates the antiproliferative effect of DRS-B2. These results highlight the partial implication of glycosaminoglycans in the mechanism of antiproliferative action of DRS-B2. Structural analysis of DRS-B2 by circular dichroism in the presence of increasing concentration of CS-C shows that DRS-B2 adopts anα-helical structure. Finally, structure-activity-relationship studies suggest a key role of the W residue in position 3 of the DRS-B2 sequence for its antiproliferative activity.Fil: Dos Santos, Célia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centre National de la Recherche Scientifique; FranciaFil: Hamadat, Sabah. Centre National de la Recherche Scientifique; Francia. University Paris Est Creteil; FranciaFil: Le Saux, Karen. University Paris Est Creteil; FranciaFil: Newton, Clara. Centre National de la Recherche Scientifique; Francia. University Paris Est Creteil; FranciaFil: Mazouni, Meriem. Centre National de la Recherche Scientifique; Francia. University Paris Est Creteil; FranciaFil: Zargarian, Loussiné. Centre National de la Recherche Scientifique; FranciaFil: Miro-Padovani, Mickael. University Paris Est Creteil; FranciaFil: Zadigue, Patricia. University Paris Est Creteil; FranciaFil: Delbé, Jean. University Paris Est Creteil; FranciaFil: Hamma-Kourbali, Yamina. University Paris Est Creteil; FranciaFil: Amiche, Mohamed. University Paris Est Creteil; Franci

EDUCAÇÃO PATRIMONIAL E O RESGATE DOS BENS CULTURAIS FAMILIARES: INTERVENÇÃO COM CRIANÇAS E ADOLESCENTES

RESUMO: é primordial a construção de novos espaços de discussão sobre a materialidade da cultura em uma prática transdisciplinar, flertando com história oral e história cultural. Neste sentido, a presente intervenção desenvolveu a educação patrimonial para crianças e adolescentes da associação Vida Cristão, no bairro Alto Paraíso em Aparecida de Goiânia. A partir da realização de ações como oficinas, os jovens participantes puderam conhecer de forma conceitual e prática o patrimônio cultural e familiar. PALAVRAS-CHAVE: Educação patrimonial. Patrimônio Cultural. Oficina

Identification and characterization of antibacterial compound(s) of cockroaches (Periplaneta americana)

Infectious diseases remain a significant threat to human health, contributing to more than 17 million deaths, annually. With the worsening trends of drug resistance, there is a need for newer and more powerful antimicrobial agents. We hypothesized that animals living in polluted environments are potential source of antimicrobials. Under polluted milieus, organisms such as cockroaches encounter different types of microbes, including superbugs. Such creatures survive the onslaught of superbugs and are able to ward off disease by producing antimicrobial substances. Here, we characterized antibacterial properties in extracts of various body organs of cockroaches (Periplaneta americana) and showed potent antibacterial activity in crude brain extract against methicillin-resistant Staphylococcus aureus and neuropathogenic E. coli K1. The size-exclusion spin columns revealed that the active compound(s) are less than 10 kDa in molecular mass. Using cytotoxicity assays, it was observed that pre-treatment of bacteria with lysates inhibited bacteria-mediated host cell cytotoxicity. Using spectra obtained with LC-MS on Agilent 1290 infinity liquid chromatograph, coupled with an Agilent 6460 triple quadruple mass spectrometer, tissues lysates were analyzed. Among hundreds of compounds, only a few homologous compounds were identified that contained isoquinoline group, chromene derivatives, thiazine groups, imidazoles, pyrrole containing analogs, sulfonamides, furanones, flavanones, and known to possess broad-spectrum antimicrobial properties, and possess anti-inflammatory, anti-tumour, and analgesic properties. Further identification, characterization and functional studies using individual compounds can act as a breakthrough in developing novel therapeutics against various pathogens including superbugs

Innovative Overheating solution for solar thermal collector using a reflective surface included in the air gap

In this work, a new solution to prevent the overheating of solar collectors in the case of stagnation is presented. The solution proposed consists of inserting a reflective sheet inside the solar collector between the absorber and the glass cover to reduce the incoming energy by reflecting solar radiation. This protection is switched ON or OFF according to the absorber temperature. A prototype has been manufactured and tested in outside conditions and in laboratory. A numerical model of the solar collector with the protection was developed and has been validated. The calculated temperature values are very close to the measured data. The experimental and numerical results showed the good behaviour of the proposed solution

APD2: the updated antimicrobial peptide database and its application in peptide design

The antimicrobial peptide database (APD, http://aps.unmc.edu/AP/main.php) has been updated and expanded. It now hosts 1228 entries with 65 anticancer, 76 antiviral (53 anti-HIV), 327 antifungal and 944 antibacterial peptides. The second version of our database (APD2) allows users to search peptide families (e.g. bacteriocins, cyclotides, or defensins), peptide sources (e.g. fish, frogs or chicken), post-translationally modified peptides (e.g. amidation, oxidation, lipidation, glycosylation or d-amino acids), and peptide binding targets (e.g. membranes, proteins, DNA/RNA, LPS or sugars). Statistical analyses reveal that the frequently used amino acid residues (>10%) are Ala and Gly in bacterial peptides, Cys and Gly in plant peptides, Ala, Gly and Lys in insect peptides, and Leu, Ala, Gly and Lys in amphibian peptides. Using frequently occurring residues, we demonstrate database-aided peptide design in different ways. Among the three peptides designed, GLK-19 showed a higher activity against Escherichia coli than human LL-37

A Systematic Review of Influenza Epidemiology and Surveillance in the Eastern Mediterranean and North African Region

Seasonal influenza represents a huge health burden, resulting in significant mortality and morbidity. Following the 2009 H1N1 pandemic, focus has been directed on the burden of influenza globally. Country and regional disease burden estimates play important roles in helping inform decisions on national influenza intervention programmes. Despite improvements in influenza surveillance following the 2009 pandemic, many opportunities remain unexplored in the Eastern Mediterranean and North African (EMNA) region, which has a high prevalence of patients with chronic disease and thus a population at high risk of influenza complications. We conducted a systematic literature review of Embase, Medline, Scopus and the Cochrane Database of Systematic Reviews from 1 January 1998 to 31 January 2020 covering the EMNA region with the aim to describe the epidemiology of influenza in the region and assess the influenza epidemiological surveillance research landscape. Relevant data on study characteristics, population, clinical/virology characteristics and epidemiology were extracted and summarised descriptively. Of the 112 studies identified for inclusion, 90 were conducted in the Eastern Mediterranean region, 19 in North Africa and three across the EMNA region. Data were reported on 314,058 laboratory-confirmed influenza cases, 96 of which were derived from surveillance systems. Amongst the surveillance studies, the percentage of positive cases reported ranged from 1% to 100%. The predominantly identified influenza strain was strain A; H1N1 was the most prominent circulating subtype. Typing was performed in approximately 75% and subtyping in 50% of studies, respectively. Data on those considered most at risk for influenza complications were collected in 21% of studies, highlighting a regional gap for these data. Our review reveals existing gaps in regional estimates of influenza health and economic burden, hospitalisation rates and duration, and highlights the need for robust and high-quality epidemiology data to help inform public health interventions. © 2022, The Author(s)

Substrate specificity of a peptidyl-aminoacyl-l/d-isomerase from frog skin

In the skin of fire-bellied toads (Bombina species), an aminoacyl-l/d-isomerase activity is present which catalyses the post-translational isomerization of the l- to the d-form of the second residue of its substrate peptides. Previously, this new type of enzyme was studied in some detail and genes potentially coding for similar polypeptides were found to exist in several vertebrate species including man. Here, we present our studies to the substrate specificity of this isomerase using fluorescence-labeled variants of the natural substrate bombinin H with different amino acids at positions 1, 2 or 3. Surprisingly, this enzyme has a rather low selectivity for residues at position 2 where the change of chirality at the alpha-carbon takes place. In contrast, a hydrophobic amino acid at position 1 and a small one at position 3 of the substrate are essential. Interestingly, some peptides containing a Phe at position 3 also were substrates. Furthermore, we investigated the role of the amino-terminus for substrate recognition. In view of the rather broad specificity of the frog isomerase, we made a databank search for potential substrates of such an enzyme. Indeed, numerous peptides of amphibia and mammals were found which fulfill the requirements determined in this study. Expression of isomerases with similar characteristics in other species can therefore be expected to catalyze the formation of peptides containing d-amino acids