Articles de revues : « Eau (H2O) »

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Silva, Rafael Severino da, Hellen Bertoletti Barbieri, Hevelyn Savio Ferreira, Claudinei Alves da Silva et Liliane Nebo. « Otimização da extração assistida por ultrassom de compostos bioativos da espécie Caryocar brasiliense ». Research, Society and Development 10, n^o 9 (29 juillet 2021) : e41310916493. http://dx.doi.org/10.33448/rsd-v10i9.16493.

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Caryocar brasiliense, popularmente conhecido como pequi, é uma espécie que apresenta alto teor de compostos fenólicos com propriedades biológicas. Neste trabalho, o processo de extração assistida por ultrassom, de compostos bioativos das folhas do pequi, foi otimizado com planejamento fatorial Box-Behnken. Quatro variáveis independentes foram avaliadas: concentração da amostra (relação:líquido-sólido (L-S), proporção de etanol na solução (EtOH/H2O % v/v), tempo de EAU (extração assistida por ultrassom) e temperatura. A metodologia de Superfície de Resposta foi usada para apontar a variável mais importante no processo. Os resultados revelaram que a proporção EtOH/H2O (% v/v) tem o efeito mais significante na extração dos compostos fenólicos. A condição ótima para extração foi de etanol 60 %, tempo de EAU de 30 min, temperatura da EAU de 42 °C e L-S 18,7:1. Sob essas condições foram extraídos 6,30 mg EAG/g ES (n = 3) (mg de equivalente de ácido gálico/ g de extrato seco). Os valores experimentais observados confirmam a adequação do modelo empregado e seu sucesso para otimização das condições de extração.

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Kherris, Sahraoui, Djallel Zebbar, Mohamed Makhlouf, Souhila Zebbar et Kouider Mostefa. « Etude et analyse d’une machine frigorifique à absorption-diffusion solaire NH3-H2O-H2 ». Journal of Renewable Energies 15, n^o 3 (23 octobre 2023) : 373–82. http://dx.doi.org/10.54966/jreen.v15i3.328.

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Cet article est consacré à la modélisation mathématique d’un système frigorifique solaire en vue de déterminer ses paramètres énergétiques. Le système en question est à absorption-diffusion fonctionnant avec le couple ammoniac-eau et l’hydrogène comme gaz inerte. Au cours de cette étude et pour la première fois, est utilisé dans le calcul de ce type de machine, un nouveau modèle mathématique pour le calcul des propriétés thermodynamiques du couple binaire ammoniac eau. A l’issue de cette étude, une analyse comparative des résultats a été effectuée sur la base des données de Bourseau.

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Khorami, Jaleh, Réjean Beaudoin et Hugues Ménard. « Étude des mélanges eau–HF par spectroscopie infrarouge à transformée de Fourier ». Canadian Journal of Chemistry 65, n^o 4 (1 avril 1987) : 817–20. http://dx.doi.org/10.1139/v87-138.

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An analysis of the ir spectra of HF–H2O mixtures containing from 10 to 97% of HF has been used to determine the evolution of the ionic species of HF. The results indicate that water and the ions H3O+F−, H3O+, and F− are present in the solutions containing less than 46% w/w of HF. In the solutions containing at least 50% w/w of HF, bands characteristic of the ion HF2− start appearing and their intensity increases with the concentration of HF, up to a concentration of 90%. As well, polymers of (HF)n have been detected in the solutions containing the highest concentration of HF. These results can be used to explain the electrochemical behaviour of solutions of HF–H2O.

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Martínez Dueñas, William Andrés, et Geneviève Deschamps. « Quand H2O et esprit de l’eau se rencontrent ». Recherches amérindiennes au Québec 42, n^o 2-3 (2 avril 2014) : 39–47. http://dx.doi.org/10.7202/1024101ar.

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Cet article a pour objectif principal de rendre visible la coexistence d’au moins deux mondes dans la Réserve autochtone de Puracé (Resguardo Indígena de Puracé, RIP) en s’appuyant sur les informations récoltées par l’auteur dans le cadre de visites des réseaux d’approvisionnement en eau du territoire en compagnie du Conseil autochtone de Puracé (Cabildo Indígena de Puracé, CIP). Ces mondes peuvent être définis en fonction de la façon dont ils interagissent avec l’eau : d’une part, le monde moderne, où l’eau est seulement un objet (H2O), et, d’autre part, le monde pas[si] moderne puracéen, où l’eau, en plus d’être un objet, présente des caractéristiques propres au sujet, comme l’esprit et la volonté. Attirer l’attention sur la coexistence de ces mondes peut par ailleurs influencer la mise en oeuvre des interventions contemporaines du développement et des politiques publiques dans les nations considérées comme multiculturelles.

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Beaudoin, Réjean, et Hugues Ménard. « Étude des complexes fluorés et chlorés du cadmium dans les mélanges eau–HF ». Canadian Journal of Chemistry 66, n^o 2 (1 février 1988) : 236–41. http://dx.doi.org/10.1139/v88-039.

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The formation of fluoride and chloride complexes in water – hydrogen fluoride mixtures has been studied using polarography. The reduction of the complexation by the fluoride ions from CdF3−down to CdF+ is in good agreement with the reduction of the fluoride ion activity, R0(F) with increasing HF concentration. At higher HF concentration than 60%, the half-wave potential for the reduction of cadmium is shifted in a pattern that cannot be explained by fluoride in complexation. The formation of CdCl3− and CdCl42− has been observed in H2O–HF–KCl mixtures when the HF concentration was increased to 60%.

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Bouchet, R., R. Tenu et J. J. Counioux. « Étude expérimentale et modélisation des équilibres solide—liquide des binaires eau—nitrate d'yttrium, de baryum, de cuivre. Partie 1. Les systèmes binaires H2OBa(NO3)2 et H2OY(NO3)3 ». Thermochimica Acta 241 (août 1994) : 229–46. http://dx.doi.org/10.1016/0040-6031(94)87020-9.

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Hissel, J., et P. Salengros. « Nouveau mode de représentation graphique de l'équilibre calco-carbonique Application au traitement des eaux ». Revue des sciences de l'eau 15, n^o 2 (12 avril 2005) : 435–58. http://dx.doi.org/10.7202/705464ar.

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Cet article traite des problèmes liés à l'étude des équilibres calco-carboniques en limitant leur présentation à l'aspect purement graphique. Dans cette optique, on a développé un nouvel abaque original en choisissant comme coordonnées pH et [CO3 total]. La construction d'un tel abaque ne fait appel qu'à 2 lois fondamentales, à savoir : a) la relation du produit de solubilité du carbonate calcique : Ks=Y22[Ca2+[CO2-3] Cette dernière peut, moyenant l'introduction d'une variable auxiliaire : ∆=[Ca2+]-[CO3 total] se transformer en une relation équivalente plus commode pour le calcul des courbes constitutives de l'abaque. b) une deuxième relation, prenant en compte les ions H+ soit libres, soit engagés dans des combinaisons avec le groupe carbonate ou avec le solvant H2 O. Dans ce but, on introduit une concentration totale appelée acidité potentielle totale (en abrégé APT) définie de la sorte : APT=2[H2CO3]+[HCO-3]+[H2O]+[H+] En outre, on utilise une variable dérivée de APT à laquelle on a donné le nom d'acidité potentielle carbonatée et le symbole. Sa définition est la suivante : δ=2[H2CO3]+[HCO-3] Les 2 variables et APT jouissent en commun de la propriété intéressante de rester invariantes lors de la mise en équilibre de l'eau selon l'équation : CaCO3+H+⇌Ca2++HCO-3 La variable peut également être considérée comme pratiquement invariante dans le domaine des eaux naturelles. Cette propriété est mise à profit pour construire 2 réseaux de courbes constitutives de l'abaque, à savoir : a) celles satisfaisant à la condition : APT=constante. Ces dernières seront appelées "courbes d'iso-acidité b) celles répondant à la condition : ∆=constante. On les désignera sous le nom de "courbes d'iso-équilibre" L'article s'attache à décrire le mode d'utilisation de cet abaque tout en mettant en valeur sa facilité d'emploi pour l'évaluation, tant qualitative que quantitative du comportement d'une eau à l'égard du carbonate calcique. En particulier, la technique permet de visualiser les caractéristiques essentielles de l'eau telles que pH équilibrant, pH stabilisant et indice de stabilisation, caractéristiques dont la signification est précisée dans l'article. L'abaque en question, en parallèle avec un logiciel qui peut lui être associé, constitue ainsi un outil précieux tant pour caractériser une eau que pour procéder ensuite aux traitements chimiques les plus connus. Le cas du mélange d'eaux peut également être avantageusement traité par le biais de cet abaque. De nombreux exemples d'application aux traitements de l'eau sont également largement développés dans la publication. Ceux-ci devraient aider grandement ceux qui sont confrontés aux divers problèmes de l'industrie de l'eau. L'analyse graphique constitue par ailleurs une excellente introduction à la gestion informatisée plus complète de ces problèmes et dont le traitement ne pouvait trouver place dans le cadre limité de cette publication. Le lecteur désireux de poursuivre ces développements ou d'avoir accès au programme informatique complémentaire à cette étude, trouvera les indications nécessaires dans les références bibliographiques figurant en fin de l'article.

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Bugarel, Marie, Lothar Beutin et Patrick Fach. « Low-Density Macroarray Targeting Non-Locus of Enterocyte Effacement Effectors (nle Genes) and Major Virulence Factors of Shiga Toxin-Producing Escherichia coli (STEC) : a New Approach for Molecular Risk Assessment of STEC Isolates ». Applied and Environmental Microbiology 76, n^o 1 (30 octobre 2009) : 203–11. http://dx.doi.org/10.1128/aem.01921-09.

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ABSTRACT Rapid and specific detection of Shiga toxin-producing Escherichia coli (STEC) strains with a high level of virulence for humans has become a priority for public health authorities. This study reports on the development of a low-density macroarray for simultaneously testing the genes stx 1, stx 2, eae, and ehxA and six different nle genes issued from genomic islands OI-122 (ent, nleB, and nleE) and OI-71 (nleF, nleH1-2, and nleA). Various strains of E. coli isolated from the environment, food, animals, and healthy children have been compared with clinical isolates of various seropathotypes. The eae gene was detected in all enteropathogenic E. coli (EPEC) strains as well as in enterohemorrhagic E. coli (EHEC) strains, except in EHEC O91:H21 and EHEC O113:H21. The gene ehxA was more prevalent in EHEC (90%) than in STEC (42.66%) strains, in which it was unequally distributed. The nle genes were detected only in some EPEC and EHEC strains but with various distributions, showing that nle genes are strain and/or serotype specific, probably reflecting adaptation of the strains to different hosts or environmental niches. One characteristic nle gene distribution in EHEC O157:[H7], O111:[H8], O26:[H11], O103:H25, O118:[H16], O121:[H19], O5:H−, O55:H7, O123:H11, O172:H25, and O165:H25 was ent/espL2, nleB, nleE, nleF, nleH1-2, nleA. (Brackets indicate genotyping of the flic or rfb genes.) A second nle pattern (ent/espL2, nleB, nleE, nleH1-2) was characteristic of EHEC O103:H2, O145:[H28], O45:H2, and O15:H2. The presence of eae, ent/espL2, nleB, nleE, and nleH1-2 genes is a clear signature of STEC strains with high virulence for humans.

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Urusov, Andrey E., Kseniya S. Aulova, Pavel S. Dmitrenok, Valentina N. Buneva et Georgy A. Nevinsky. « EAE of Mice : Enzymatic Cross Site-Specific Hydrolysis of H2A Histone by IgGs against H2A, H1, H2B, H3, and H4 Histones and Myelin Basic Protein ». International Journal of Molecular Sciences 24, n^o 10 (12 mai 2023) : 8636. http://dx.doi.org/10.3390/ijms24108636.

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Histones play vital roles in chromatin function and gene transcription; however, they are very harmful in the intercellular space because they stimulate systemic inflammatory and toxic responses. Myelin basic protein (MBP) is the major protein of the axon myelin–proteolipid sheath. Antibodies–abzymes with various catalytic activities are specific features of some autoimmune diseases. IgGs against individual histones (H2A, H1, H2B, H3, and H4) and MBP were isolated from the blood of experimental-autoimmune-encephalomyelitis-prone C57BL/6 mice by several affinity chromatographies. These Abs–abzymes corresponded to various stages of EAE development: spontaneous EAE, MOG, and DNA–histones accelerated the onset, acute, and remission stages. IgGs-abzymes against MBP and five individual histones showed unusual polyreactivity in the complex formation and enzymatic cross-reactivity in the specific hydrolysis of the H2A histone. All the IgGs of 3-month-old mice (zero time) against MBP and individual histones demonstrated from 4 to 35 different H2A hydrolysis sites. The spontaneous development of EAE over 60 days led to a significant change in the type and number of H2A histone hydrolysis sites by IgGs against five histones and MBP. Mice treatment with MOG and the DNA–histone complex changed the type and number of H2A hydrolysis sites compared to zero time. The minimum number (4) of different H2A hydrolysis sites was found for IgGs against H2A (zero time), while the maximum (35) for anti-H2B IgGs (60 days after mice treatment with DNA–histone complex). Overall, it was first demonstrated that at different stages of EAE evolution, IgGs–abzymes against individual histones and MBP could significantly differ in the number and type of specific sites of H2A hydrolysis. The possible reasons for the catalytic cross-reactivity and great differences in the number and type of histone H2A cleavage sites were analyzed.

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Mora, Azucena, Cecilia López, Ghizlane Dhabi, Ana M. López-Beceiro, Luís E. Fidalgo, Eduardo A. Díaz, Carlos Martínez-Carrasco et al. « Seropathotypes, Phylogroups, Stx Subtypes, and Intimin Types of Wildlife-Carried, Shiga Toxin-Producing Escherichia coli Strains with the Same Characteristics as Human-Pathogenic Isolates ». Applied and Environmental Microbiology 78, n^o 8 (3 février 2012) : 2578–85. http://dx.doi.org/10.1128/aem.07520-11.

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ABSTRACTThe objectives of this study were to investigate the presence of Shiga toxin-producingEscherichia coli(STEC) strains in wildlife that have spread in Europe, living near human settlements; to analyze their epidemiological role in maintenance and transmission to domestic livestock; and to assess the potential health risk of wildlife-carried strains. STEC strains were recovered from 53% of roe deer, 8.4% of wild boars, and 1.9% of foxes sampled in the northwest of Spain (Galicia). Of the 40 serotypes identified, 21 were classified as seropathotypes associated with human disease, accounting for 81.5% of the wildlife-carried STEC strains, including the enterohemorrhagic serotypes O157:H7-D-eae-γ1, O26:[H11]-B1-eae-β1, O121:H19-B1-eae-ε1, and O145:[H28]-D-eae-γ1. None of the wildlife-carried strains belonged to the highly pathogenic serotype O104:H4-B1 from the recent Germany outbreak. Forty percent of wildlife-carried STEC strains shared serotypes, phylogroups, intimin types, and Stx profiles with isolates from human patients from the same geographic area. Furthermore, wildlife-carried strains belonging to serotypes O5:HNM-A, O26:[H11]-B1, O76:H19-B1, O145:[H28]-D, O146:H21-B1, and O157:H7-D showed pulsed-field gel electrophoresis (PFGE) profiles with >85% similarity to human-pathogenic STEC strains. We also found a high level of similarity among STEC strains of serotypes O5:HNM-A, O26:[H11]-B1, and O145:HNM-D of bovine (feces and beef) and wildlife origins. Interestingly, O146:H21-B1, the second most frequently detected serotype in this study, is commonly associated with human diarrhea and isolated from beef and vegetables sold in Galicia. Importantly, at least 3 STEC isolates from foxes (O5:HNM-A-eae-β1, O98:[H21]-B1-eae-ζ1, and O146:[H21]-B1) showed characteristics similar to those of human STEC strains. In conclusion, roe deer, wild boar, and fox in Galicia are confirmed to be carriers of STEC strains potentially pathogenic for humans and seem to play an important role in the maintenance of STEC.

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Zhou, Mingming, Jing Luo et Dong Xiang. « Effects of Different Guests on Pyrolysis Mechanism of α-CL−20/Guest at High Temperatures by Reactive Molecular Dynamics Simulations at High Temperatures ». International Journal of Molecular Sciences 24, n^o 3 (17 janvier 2023) : 1840. http://dx.doi.org/10.3390/ijms24031840.

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The host–guest inclusion strategy has the potential to surpass the limitations of energy density and suboptimal performances of single explosives. The guest molecules can not only enhance the detonation performance of host explosives but also can enhance their stability. Therefore, a deep analysis of the role of guest influence on the pyrolysis decomposition of the host–guest explosive is necessary. The whole decomposition reaction stage of CL-20/H2O, CL-20/CO2, CL-20/N2O, CL-20/NH2OH was calculated by ReaxFF-MD. The incorporation of CO2, N2O and NH2OH significantly increase the energy levels of CL-20. However, different guests have little influence on the initial decomposition paths of CL-20. The Ea1 and Ea2 values of CL-20/CO2, CL-20/N2O, CL-20/NH2OH systems are higher than the CL-20/H2O system. Clearly, incorporation of CO2, N2O, NH2OH can inhibit the initial decomposition and intermediate decomposition stage of CL-20/H2O. Guest molecules become heavily involved in the reaction and influence on the reaction rates. k1 of CL-20/N2O and CL-20/NH2OH systems are significantly larger than that of CL-20/H2O at high temperatures. k1 of CL-20/CO2 system is very complex, which can be affected deeply by temperatures. k2 of the CL-20/CO2, CL-20/N2O systems is significantly smaller than that of CL-20/H2O at high temperatures. k2 of CL-20/NH2OH system shows little difference at high temperatures. For the CL-20/CO2 system, the k3 value of CO2 is slightly higher than that for CL-20/H2O, CL-20/N2O, CL-20/NH2OH systems, while the k3 values of N2 and H2O are slightly smaller than that for the CL-20/H2O, CL-20/N2O, CL-20/NH2OH systems. For the CL-20/N2O system, the k3 value of CO2 is slightly smaller than that for CL-20/H2O, CL-20/CO2, CL-20/NH2OH systems. For the CL-20/NH2OH system, the k3 value of H2O is slightly larger than that for CL-20/H2O, CL-20/CO2, CL-20/N2O systems. These mechanisms revealed that CO2, N2O and NH2OH molecules inhibit the early stages of the initial decomposition of CL-20 and play an important role for the decomposition subsequently.

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Cavanaugh, Robert M. « Pediatricians and the Pneumatic Otoscope : Are We Playing It By Ear ? » Pediatrics 84, n^o 2 (1 août 1989) : 362–64. http://dx.doi.org/10.1542/peds.84.2.362.

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The amount of positive pressure delivered during pneumatic otoscopy was recorded in 53 healthy pediatric patients. The pressures generated ranged from 338 to 1134 mm H2O. The mean pressure introduced was 748 mm H2O with the bulb and 502 mm H2O through the mouthpiece. The mean intraobserver variation in pressure delivered to each patient was 199 and 125 mm H2O with these two methods of insufflation, respectively. These data document the wide variation in pressures generated with the pneumatic otoscope and suggest that the feasibility of modifying this instrument into a standardized, objective pneumatic system should be explored.

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Urusov, Andrey E., Kseniya S. Aulova, Pavel S. Dmitrenok, Valentina N. Buneva et Georgy A. Nevinsky. « EAE of Mice : Enzymatic Cross Site-Specific Hydrolysis of H2B Histone by IgGs against H1, H2A, H2B, H3, and H4 Histones and Myelin Basic Protein ». Molecules 28, n^o 7 (27 mars 2023) : 2973. http://dx.doi.org/10.3390/molecules28072973.

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Histones have vital roles in chromatin functioning and gene transcription. At the same time, they are pernicious in intercellular space because they stimulate systemic inflammatory and toxic responses. Myelin basic protein (MBP) is the major protein of the axon myelin–proteolipid sheath. Antibody-abzymes with various catalytic activities are specific features of some autoimmune diseases. IgGs against five individual histones (H2B, H1, H2A, H3, and H4) and MBP were isolated from the blood of experimental autoimmune encephalomyelitis-prone C57BL/6 mice by affinity chromatography. Abzymes corresponding to various stages of EAE development, including spontaneous EAE, myelin oligodendrocyte glycoprotein (MOG)- and DNA-histone complex-accelerated onset, as well as acute and remission stages, were analyzed. IgG-abzymes against MBP and five individual histones showed unusual polyreactivity in complex formation and enzymatic cross-reactivity in the specific hydrolysis of H2B histone. All IgGs against MBP and individual histones in 3-month-old mice (zero time) demonstrated from 4 to 11 different H2B hydrolysis sites. Spontaneous development of EAE during 60 days led to a significant change in the type and number of H2B hydrolysis sites by IgGs against the five histones and MBP. Mouse treatment with MOG and DNA-histone complex changed the type and number of H2B hydrolysis sites compared to zero time. The minimum number (3) of different H2B hydrolysis sites was found for IgGs against H3 20 days after mouse immunization with DNA-histone complex, whereas the maximum number (33) for anti-H2B IgGs was found 60 days after mouse treatment with DNA-histone complex. Overall, this is the first study to demonstrate that at different stages of EAE evolution, IgG-abzymes against five individual histones and MBP could significantly differ in the specific sites and number of H2B hydrolysis sites. Possible reasons for the catalytic cross-reactivity and significant differences in the number and type of histone H2B cleavage sites were analyzed.

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Walsh, A. J., S. L. Breen, T. Britton, K. J. Brooks, M. G. Burton, M. R. Cunningham, J. A. Green et al. « HOPS : The H2O Southern Galactic Plane Survey ». EAS Publications Series 52 (2011) : 135–38. http://dx.doi.org/10.1051/eas/1152021.

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Jeong, Myeongguk, Hyeokjin Kwon, Yeeun Kim, Hyunwoo Jin, Go-Eun Choi et Kyung-Yae Hyun. « Erigeron annuus Extract Improves DNCB-Induced Atopic Dermatitis in a Mouse Model via the Nrf2/HO-1 Pathway ». Nutrients 16, n^o 3 (3 février 2024) : 451. http://dx.doi.org/10.3390/nu16030451.

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Atopic dermatitis (AD) is a persistent inflammatory skin condition resulting from an intricate interplay among genetic, immunological, and environmental factors. Erigeron annuus (EA), an annual winter plant belonging to the family Asteraceae, possesses anti-inflammatory, cytoprotective, and antioxidant activities. In this study, we hypothesized that Erigeron annuus extract (EAE) could be an effective agent for ameliorating AD-like symptoms. To confirm this hypothesis in vitro, we used H2O2-stimulated human keratinocytes (HaCaT cells) to demonstrate that pre-treatment with EAE protected against oxidative stress. HaCaT cells pretreated with EAE and stimulated with H2O2 showed decreased intracellular malondialdehyde content, increased superoxide dismutase activity, and reduced intracellular reactive oxygen species accumulation. To verify the in vivo hypothesis based on the intracellular results, an AD disease mouse model was induced with 1-chloro-2,4-dinitrobenzene (DNCB), and EAE was orally administered at a non-toxic concentration according to the toxicity evaluation results. The results showed that AD disease models in BALB/c mice exhibited reduced ear epidermal thickness, scratching behavior, and mast cell infiltration. In conclusion, our results indicate that EAE has the potential to improve AD by upregulating the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway.

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Wu, Wei Dong, Zeng Yang Li, Sheng Xiang Chen et Si Mei Liu. « Experimental Study on Ammonia-Water Bubble Absorption in External Magnetic Field ». Advanced Materials Research 291-294 (juillet 2011) : 1653–56. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.1653.

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Absorber is a key component of absorption refrigeration system, in which there is a complicated heat and mass transfer. To improve the performance of absorber, the magnetic field was used as a enhancing way, the experiments of NH3/H2O bubble absorption in magnetic field were carried out. The results showed that the NH3/H2O bubble absorption can be strengthened by the magnetic field. Both AR(absorption rate) and EAR(effective absorption ratio) increase with the increase of magnetic intensity within the range of 0~280mT. The EAR is always higher than 1 when the external magnetic field exists. The EAR reaches the maximum 1.069 when the initial ammonia concentration is 20wt% and the magnetic intensity is 280mT. The primary strengthening mechanisms are also explained.

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Kimitsuki, Takashi. « The effect of pressure on potassium currents in the inner hair cells isolated from guinea-pig cochlea ». Acta Neurobiologiae Experimentalis 73, n^o 4 (31 décembre 2013) : 521–28. http://dx.doi.org/10.55782/ane-2013-1956.

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An increase in hydrostatic pressure in the endolymphatic system causes hydrops-related inner ear diseases such as Meniere’s disease or low tone sensorineural hearing loss. In the present study, we investigated the effects of pressure exerted on potassium currents in acutely isolated inner hair cells of the guinea-pig cochlea using whole-cell voltage-clamp techniques. By applying negative or positive pressure via the patch pipette using a syringe, intracellular hydropressure was changed between −40 cm H2O to +20 cm H2O. Negative pressure potentiated the amplitude of potassium currents, whereas positive pressure suppressed the amplitude of potassium currents. Gadolinium, a blocker of stretch-activated cation channels, did not influence pressure-dependent changes in potassium currents; however, cinnarizine blocked pressure-dependent changes in potassium currents. The current changes were not dependent on the sign of the pressure change, that is, similar increases in negative pressures (between −10 cm H2O and −40 cm H2O) and similar decreases in positive pressures (between +10 cm H2O and +20 cm H2O) were observed.

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Jumaeva, Dilnoza, Olimjon Toirov, Nigora Rakhmatullaeva Ravshan Akhmedov et Izzat Eshmetov. « Energy of adsorption of polar molecules on NaLSX zeolite ». E3S Web of Conferences 288 (2021) : 01041. http://dx.doi.org/10.1051/e3sconf/202128801041.

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The article presents precision data of isotherms and total thermodynamic characteristics, i.e. ΔH, ΔF and ΔS of H2O adsorption on NaLSX zeolite. The stepwise nature of the change in the heat of adsorption on the studied systems with surface filling is revealed, and the molecular mechanism of water adsorption on NaLSX zeolite in the entire filling area is revealed. It was found that the polar water molecule is adsorbed in the NaLSX zeolite in an amount of 31.8 H2O/1/8 e.u., of which 25.3 are in super cavities, and 6.5 are in β-cavities.

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Miko, Angelika, Karin Pries, Sabine Haby, Katja Steege, Nadine Albrecht, Gladys Krause et Lothar Beutin. « Assessment of Shiga Toxin-Producing Escherichia coli Isolates from Wildlife Meat as Potential Pathogens for Humans ». Applied and Environmental Microbiology 75, n^o 20 (21 août 2009) : 6462–70. http://dx.doi.org/10.1128/aem.00904-09.

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ABSTRACT A total of 140 Shiga toxin-producing Escherichia coli (STEC) strains from wildlife meat (deer, wild boar, and hare) isolated in Germany between 1998 and 2006 were characterized with respect to their serotypes and virulence markers associated with human pathogenicity. The strains grouped into 38 serotypes, but eight O groups (21, 146, 128, 113, 22, 88, 6, and 91) and four H types (21, 28, 2, and 8) accounted for 71.4% and 75.7% of all STEC strains from game, respectively. Eighteen of the serotypes, including enterohemorrhagic E. coli (EHEC) O26:[H11] and O103:H2, were previously found to be associated with human illness. Genes linked to high-level virulence for humans (stx 2, stx 2d, and eae) were present in 46 (32.8%) STEC strains from game. Fifty-four STEC isolates from game belonged to serotypes which are frequently found in human patients (O103:H2, O26:H11, O113:H21, O91:H21, O128:H2, O146:H21, and O146:H28). These 54 STEC isolates were compared with 101 STEC isolates belonging to the same serotypes isolated from farm animals, from their food products, and from human patients. Within a given serotype, most STEC strains were similar with respect to their stx genotypes and other virulence attributes, regardless of origin. The 155 STEC strains were analyzed for genetic similarity by XbaI pulsed-field gel electrophoresis. O103:H2, O26:H11, O113:H21, O128:H2, and O146:H28 STEC isolates from game were 85 to 100% similar to STEC isolates of the same strains from human patients. By multilocus sequence typing, game EHEC O103:H2 strains were attributed to a clonal lineage associated with hemorrhagic diseases in humans. The results from our study indicate that game animals represent a reservoir for and a potential source of human pathogenic STEC and EHEC strains.

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Dias, Ângela Maria Girardi, Kinue Irino, Elena Kano, Maria Aidê Mitiko Fukushima Kato, Tânia Aparecida Tardelo Gomes et Luiz Rachid Trabulsi. « Diversidade dos genes associados à virulência em cepas de Escherichia coli O128 isoladas em São Paulo, Brasil ». Revista do Instituto Adolfo Lutz 67, n^o 2 (1 avril 2008) : 156–62. http://dx.doi.org/10.53393/rial.2008.67.32784.

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Foram estudadas 103 cepas de Escherichia coli do sorogrupo O128, quanto às características fenotípicas e genotípicas associadas à virulência. Cinqüenta e nove cepas representantes de todos os sorotipos foram submetidas a ribotipagem. Os sorotipos mais freqüentes foram O128:H35 (41,7%), O128:H2 (14,6%), O128:H- (8,7%) e O128:H8 (6,8%). Diferentes grupos enteropatogênicos foram identificados. Somente as cepas do sorotipo O128:H2 foram positivas para as sondas eae and bfpA e apresentaram o padrão de adesão AL-like. Cepas do sorotipo O128:H8 e algumas imóveis reagiram apenas com a sonda eae e foram classificadas como EPEC atípicas. As cepas O128:H35 corresponderam à categoria enteroagregativa e os sorotipos O128:H7, O128:H21, O128:H27 e as cepas imóveis foram classificadas como enterotoxigênicas. Todas as cepas que apresentaram marcadores de virulência pertenciam ao grupo clonal A, enquanto que no grupo clonal B estavam incluídas as cepas desprovidas dos fatores de virulência pesquisados.

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van der Tak, F., F. Herpin et F. Wyrowski. « Herschel-HIFI observations of H2O in high-mass star-forming regions : first results ». EAS Publications Series 52 (2011) : 201–4. http://dx.doi.org/10.1051/eas/1152033.

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Abdul-Baqi, Khader J. « Chloral hydrate and middle ear pressure ». Journal of Laryngology & ; Otology 105, n^o 6 (juin 1991) : 421–23. http://dx.doi.org/10.1017/s0022215100116196.

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AbstractMiddle ear pressure and tympanic membrane compliance were measured in 34 infants and young children (66 ears) with normal middle ears under oral choral hydrate hypnosis. Tympanograms were performed before and 40 to 60 minutes after administration of the drug. Results showed that the middle ear pressure increased significantly in all cases and in both sexes. This increase ranged between +19 and +219 mm H2O. In all cases the pressure returned to its prehypnotic values after recovery. Results of tympanic membrane compliance showed significant increase in males and not significant decrease in females.

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Mottram, J. C., E. F. van Dishoeck, L. E. Kristensen et I. San José-García. « Life in the fast lane : H2O reveals the universal nature of shocks in outflows ». EAS Publications Series 75-76 (2015) : 195–97. http://dx.doi.org/10.1051/eas/1575037.

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Kawana, Masahiro, Chihiro Kawana, Steven K. Juhn, Ryo Amesara et G. Scott Giebink. « Neutrophil Oxygen Metabolite Inhibition of Cultured Chinchilla Middle Ear Epithelial Cell Growth ». Annals of Otology, Rhinology & ; Laryngology 103, n^o 10 (octobre 1994) : 812–16. http://dx.doi.org/10.1177/000348949410301012.

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Middle ear inflammation in acute bacterial otitis media is characterized by accumulation of neutrophils in middle ear effusion. Since neutrophils release products that may injure surrounding tissues, we studied the effect of neutrophil metabolic products on middle ear epithelial cells (MEECs) in vitro. Chinchilla MEECs were incubated with phorbol myristate acetate (PMA)–activated human neutrophils or with hydrogen peroxide (H2O2). Cell growth, which was measured by 3H-thymidine incorporation, was inhibited by activated neutrophils and by H2O2. Unstimulated neutrophils, PMA alone, and catalase alone did not affect the viability of MEECs. Catalase, an enzyme that reduces H2O2, partially blocked the inhibitory effect of activated neutrophils and completely blocked the inhibitory effect of H2O2. Inhibition of MEEC metabolism by neutrophil-reactive oxygen species may contribute to epithelial injury, which may prolong the middle ear inflammatory response and lead to chronic tissue damage.

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Bielaszewska, Martina, Marina Fell, Lilo Greune, Rita Prager, Angelika Fruth, Helmut Tschäpe, M. Alexander Schmidt et Helge Karch. « Characterization of Cytolethal Distending Toxin Genes and Expression in Shiga Toxin-Producing Escherichia coli Strains of Non-O157 Serogroups ». Infection and Immunity 72, n^o 3 (mars 2004) : 1812–16. http://dx.doi.org/10.1128/iai.72.3.1812-1816.2004.

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ABSTRACT We identified cytolethal distending toxin and its gene (cdt) in 17 of 340 non-O157 Shiga toxin-producing Escherichia coli (STEC) strains (serotypes O73:H18, O91:H21, O113:H21, and O153:H18), all of which were eae negative. cdt is either chromosomal and homologous to cdt-V (serotypes O73:H18, O91:H21, and O113:H21) or plasmidborne and identical to cdt-III (serotype O153:H18). Among eae-negative STEC, cdt was associated with disease (P = 0.003).

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Carbonari, Claudia Carolina, Elizabeth Sandra Miliwebsky, Gisela Zolezzi, Natalia Lorena Deza, Nahuel Fittipaldi, Eduardo Manfredi, Ariela Baschkier et al. « The Importance of Shiga Toxin-Producing Escherichia coli O145:NM[H28]/H28 Infections in Argentina, 1998–2020 ». Microorganisms 10, n^o 3 (7 mars 2022) : 582. http://dx.doi.org/10.3390/microorganisms10030582.

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Shiga toxin-producing Escherichia coli (STEC) is known as a pathogen associated with food-borne diseases. The STEC O145 serogroup has been related with acute watery diarrhea, bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Argentina has the highest rate of HUS worldwide with 70% of the cases associated with STEC infections. We aimed to describe the epidemiology and genetic diversity of STEC O145 strains isolated across Argentina between 1998–2020. The strains isolated from 543 cases of human disease and four cattle, were pheno-genotipically characterized. Sequencing of five strains was performed. The strains were serotyped as O145:NM[H28]/H28, O145:H25, and O145:HNT, and mainly characterized as O145:NM[H28]/stx2a/eae/ehxA (98.1%). The results obtained by sequencing were consistent with those obtained by traditional methods and additional genes involved in different mechanisms of the pathogen were observed. In this study, we confirmed that STEC O145 strains are the second serogroup after O157 and represent 20.3% of HUS cases in Argentina. The frequency of STEC O145 and other significant serogroups is of utmost importance for public health in the country. This study encourages the improvement of the surveillance system to prevent severe cases of human disease.

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Osmanova, S. N., U. A. Kerimova, N. S. Osmanov, E. H. Ismailov et S. A. Suleymanova. « DYNAMIC LIGHT SCATTERING BY NANO- AND MICRO-SIZED COMPLEXES IN THE SYSTEM K2ReBr6/p-AMINOBENZOIC ACID/HBr/H2O ». JOURNAL OF ADVANCES IN CHEMISTRY 11, n^o 3 (3 avril 2015) : 3375–80. http://dx.doi.org/10.24297/jac.v11i3.865.

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K2ReBr6/p-aminobenzoic acid/HBr/H2O system using dynamic light scattering (DLS) and electronic absorption spectra (EAS) were studied. The formation of nano- and micro-sized complexes with hydrodynamic radius 0.001-2.8 µm within the temperature interval 293-333 K and as a function of concentration of hydrobromic acid and K2ReBr6/p-aminobenzoic acid ratio are shown.

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Szczerba-Turek, Anna, Filomena Chierchia, Piotr Socha et Wojciech Szweda. « Shiga Toxin-Producing Escherichia coli in Faecal Samples from Wild Ruminants ». Animals 13, n^o 5 (1 mars 2023) : 901. http://dx.doi.org/10.3390/ani13050901.

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Wildlife can harbour Shiga toxin-producing Escherichia coli (STEC). In the present study, STEC in faecal samples from red deer (n = 106) and roe deer (n = 95) were characterised. All isolates were non-O157 strains. In red deer, STEC were detected in 17.9% (n = 19) of the isolates, and the eae/stx2b virulence profile was detected in two isolates (10.5%). One STEC strain harboured stx1a (5.3%) and eighteen STEC strains harboured stx2 (94.7%). The most prevalent stx2 subtypes were stx2b (n = 12; 66.7%), stx2a (n = 3; 16.7%), and stx2g (n = 2; 11.1%). One isolate could not be subtyped (NS) with the applied primers (5.6%). The most widely identified serotypes were O146:H28 (n = 4; 21%), O146:HNM (n = 2; 10.5%), O103:H7 (n = 1; 5.3%), O103:H21 (n = 1; 5.3%), and O45:HNM (n = 1; 5.3%). In roe deer, STEC were detected in 16.8% (n = 16) of the isolates, and the eae/stx2b virulence profile was detected in one isolate (6.3%). Two STEC strains harboured stx1a (12.5%), one strain harboured stx1NS/stx2b (6.3%), and thirteen strains harboured stx2 (81.3%). The most common subtypes were stx2b (n = 8; 61.5%), stx2g (n = 2; 15.4%), non-typeable subtypes (NS) (n = 2; 15.4%), and stx2a (n = 1; 7.7%). Serotype O146:H28 (n = 5; 31.3%) was identified. The study demonstrated that the zoonotic potential of STEC strains isolated from wildlife faeces should be monitored in the context of the ‘One Health’ approach which links human health with animal and environmental health.

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Furuya, K., M. N. Drozdovskaya, C. Walsh et E. F. van Dishoeck. « Water transport from collapsing prestellar cores to forming disks : evolution of the HDO/H2O ratio ». EAS Publications Series 75-76 (2015) : 259–63. http://dx.doi.org/10.1051/eas/1575051.

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McGarvey, Stephen T., Justin Buszin, Holly Reed, David C. Smith, Zarah Rahman, Catherine Andrzejewski, Kofi Awusabo-Asare et Michael J. White. « Community and household determinants of water quality in coastal Ghana ». Journal of Water and Health 6, n^o 3 (1 mars 2008) : 339–49. http://dx.doi.org/10.2166/wh.2008.057.

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Associations between water sources, socio-demographic characteristics and household drinking water quality are described in a representative sample of six coastal districts of Ghana's Central Region. Thirty-six enumeration areas (EAs) were randomly chosen from a representative survey of 90 EAs in rural, semi-urban and urban residence strata. In each EA, 24 households were randomly chosen for water quality sampling and socio-demographic interview. Escherichia coli per 100 ml H2O was quantified using the IDEXX Colilert® system and multi-stage regression models estimated cross-sectional associations between water sources, sanitation and socio-demographic factors. Almost three quarters, 74%, of the households have >2 E. coli /100 ml H2O. Tap water has significantly lower E. coli levels compared with surface or rainwater and well water had the highest levels. Households with a water closet toilet have significantly lower E. coli compared with those using pit latrines or no toilets. Household size is positively associated, and a possessions index is negatively associated, with E. coli. Variations in community and household socio-demographic and behavioural factors are key determinants of drinking water quality. These factors should be included in planning health education associated with investments in water systems.

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Takahashi, Haruo, Masahiko Hayashi, Iwao Honjo et Akihiko Fujita. « Clearance Function of Eustachian Tube and Negative Middle Ear Pressure ». Annals of Otology, Rhinology & ; Laryngology 101, n^o 9 (septembre 1992) : 759–62. http://dx.doi.org/10.1177/000348949210100908.

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Two experimental studies were performed using 18 cats in order to elucidate the mechanism of the long-lasting course of otitis media with effusion. First, the middle ear (ME) pressure was monitored for 2.5 to 7 hours after filling the whole ME space with saline. On average, −150 mm H2O of negative ME pressure was induced in 3.1 hours. Second, the residual volume of saline with antibiotics, which was put into the ME space 2 to 7 days before, was compared between the side on which tubal ventilatory function was abolished (resection of tensor veli palatini muscle and hamulus pterygoideus) and the opposite, control side. The percentage of the residual volume to the original volume put into the ME was significantly higher on the experimental side (Wilcoxon's ranking test, t = 27.0, p < .05), and in one ear on the experimental side, the ME pressure showed −150 mm H2O just before the bulla was opened 2 to 7 days later. These results seem to indicate that tubal ciliary clearance function can induce negative ME pressure when there is fluid in the ME, and that the negative ME pressure induced by clearance of the ME fluid may disturb further clearance of the ME fluid. This condition may cause the long-lasting course of otitis media with effusion.

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Myers, Eugene N., Shingo Murakami, Kiyofumi Gyo et Richard L. Goode. « Effect of Increased Inner Ear Pressure on Middle Ear Mechanics ». Otolaryngology–Head and Neck Surgery 118, n^o 5 (mai 1998) : 703–8. http://dx.doi.org/10.1177/019459989811800528.

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Velocity of malleus, umbo, and stapes footplate in response to stepwise increases up to +400 mm H2O in hydrostatic pressure of the inner ear was investigated in 10 fresh human temporal bones by using a laser Doppler interferometer. The sound-pressure input was 114 dB SPL, and the frequency range was 0.4 to 5.0 kHz. Static displacement of these sites was also measured by a video measuring system. When the inner ear pressure was increased, the malleus and stapes moved outward. Amplitude of umbo velocity decreased below 1.0 kHz with a slight increase around 2.0 kHz, whereas stapes velocity decreased at all frequencies with the major effect below 1.0 kHz. The phase angle of malleus umbo velocity advanced markedly in response to the increased inner ear pressure between 1.0 and 1.4 kHz. Change in the vibration of the umbo was thought to be primarily caused by an increased stiffness of the middle ear conduction system, and that of the stapes was caused by distention of the annular ligament and increased cochlear impedance produced by the increased inner ear pressure. These changes in TM vibration and its phase angle may help detect indirectly an elevation of inner ear pressure. (Otolaryngol Head Neck Surg 1998;118:703–8.)

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Pringle, M. B. « Grommets, swimming and otorrhoea — a review ». Journal of Laryngology & ; Otology 107, n^o 3 (mars 1993) : 190–94. http://dx.doi.org/10.1017/s0022215100122601.

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Ever since Armstrong reintroduced the concept co grommeet insertion parents have been asking ‘may my child swim?’, yet there is still no consensus as to the correct answer. This paper reviews the work that has been done on this subject in the last 25 years. A review of teh reates of otorrhoea following grommet insertion, irrespective of swimming, shows a variation from 12 to 64 per cent. Evidence suggests that pressures of 12–23 cm H2O are needed to push water through a grommeet and that it is unlikely that water will enter the middle ear during surface swimming. Only bath water seems to cause significant inflammtory changes to middle ear mucosa. Not a single paper comparing swimming without ear protection can be safely permitted for children with grommets.

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Urusov, Andrey E., Kseniya S. Aulova, Pavel S. Dmitrenok, Valentina N. Buneva et Georgy A. Nevinsky. « Experimental Autoimmune Encephalomyelitis of Mice : Enzymatic Cross Site-Specific Hydrolysis of H4 Histone by IgGs against Histones and Myelin Basic Protein ». International Journal of Molecular Sciences 23, n^o 16 (16 août 2022) : 9182. http://dx.doi.org/10.3390/ijms23169182.

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Histones play vital roles in chromatin functioning and gene transcription, but in intercellular space, they are harmful due to stimulating systemic inflammatory and toxic responses. Myelin basic protein (MBP) is the most important protein of the axon myelin–proteolipid sheath. Antibodies-abzymes with different catalytic activities are critical and specific features of some autoimmune diseases. Five IgG preparations against histones (H4, H1, H2A, H2B, and H3) and against MBP corresponding to different spontaneous, MOG (myelin oligodendrocyte glycoprotein of mice), and DNA–histones that accelerated onset, acute, and remission stages of experimental autoimmune encephalomyelitis (EAE; model of human multiple sclerosis) development were obtained from EAE-prone C57BL/6 mice by several affinity chromatographies. IgG-abzymes against five histones and MBP possess unusual polyreactivity in complexation and catalytic cross-reactivity in the hydrolysis of histone H4. IgGs against five histones and MBP corresponding to 3 month-old mice (zero time) in comparison with Abs corresponding to spontaneous development of EAE during 60 days differ in type and number of H4 sites for hydrolysis. Immunization of mice with MOG and DNA–histones complex results in an acceleration of EAE development associated with an increase in the activity of antibodies in H4 hydrolysis. Twenty days after mouse immunization with MOG or DNA–histones complex, the IgGs hydrolyze H4 at other additional sites compared to zero time. The maximum number of different sites of H4 hydrolysis was revealed for IgGs against five histones and MBP at 60 days after immunization of mice with MOG and DNA–histones. Overall, it first showed that at different stages of EAE development, abzymes could significantly differ in specific sites of H4 hydrolysis.

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刘, 红霞. « Treatment of Primary Supraorbital Neuralgia with Ear-Apex Blood-Letting ». Hans Journal of Ophthalmology 06, n^o 02 (2017) : 41–44. http://dx.doi.org/10.12677/hjo.2017.62009.

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Ellis, E. Ann, et John R. Guy. « Localization of hydrogen peroxide and serum albumin in experimental optic neuritis : Combined cytochemistry amd immunocytochemistry ». Proceedings, annual meeting, Electron Microscopy Society of America 50, n^o 1 (août 1992) : 808–9. http://dx.doi.org/10.1017/s0424820100124446.

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The oxidant, hydrogen peroxide (H2O2), is discharged by inflammatory cells that infiltrate the central nervous system and has been shown to play a role in disruption of the blood-brain barrier (BBB) and demyelination in the optic neuritis of experimental allergic encephalomyelitis (EAE)1, an animal model for multiple sclerosis (MS). Alterations in the BBB and vascular permeability in EAE have been studied with exogenous, injected tracers; but there have been no studies of native, endogenous proteins. In order to study the role of oxidants in vascular permeability in EAE, we localized H2O2 at the ultrastructural level followed by immunocytochemical localization of endogenous serum albumin in the optic nerves of guinea pigs sensitized to EAE.

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Bruns, H. Arnold. « Ear Leaf Photosynthesis and Related Parameters of Transgenic and Non-GMO Maize Hybrids ». International Journal of Agronomy 2015 (2015) : 1–5. http://dx.doi.org/10.1155/2015/731351.

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Hybrid maize (Zea maysL.) through transgenics now includesδ-endotoxins for insect control and tolerance to the herbicides glyphosate and glufosinate. Some hybrids have multiple transgenic traits as part of their genotype (stacked gene). Limited information is available on how these traits alone affectA(net assimilation rate;µmol CO2m−2s−1) and related physiological parameters. A two-year, two-location, irrigated experiment comparing four stacked gene, four glyphosate tolerant, and two non-GMO hybrids for ear leafA,gs(stomatal conductance; mol H2O m−2s−1),Em(transpiration; mol H2O m−2s−1), IWUE (intrinsic water use efficiency;(A/(gs*100))), and Ci(intercellular [CO2]µmol CO2mol air−1) was completed at Stoneville, MS, in 2012. Data were collected at growth stages R1 (anthesis) and R2 (early kernel filling) using a Li-Cor LI-6400XT set at 355 μmol mol−1CO2with a flow rate of 500 μmol s−1and a 6400-02 light source set at 87.5% full sunlight. Measurements were made between 08:30 h and 11:30 h CST, within 48 h of 25 ha mm irrigation and ≥33.0% cloud cover. Transgenic traits did not influence the physiological parameters ofA,gs,Em, IWUE, or Ciduring the critical growth stages of R1 or R2.

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Bevan, J. A., et E. H. Joyce. « Saline infusion into lumen of resistance artery and small vein causes contraction ». American Journal of Physiology-Heart and Circulatory Physiology 259, n^o 1 (1 juillet 1990) : H23—H28. http://dx.doi.org/10.1152/ajpheart.1990.259.1.h23.

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Infusion of saline into the lumen of a resistance artery from the rabbit ear at rates between 0.5 and 20 microliters/min causes a rate-dependent maintained contraction. This contraction is independent of the direction of saline flow and of the endothelium. The contraction is prevented by pretreatment with the vasodilator papaverine (0.1 mM), which also reversed the contraction during flow. Exclusion of calcium from the physiological saline solution plus ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (1 mM) prevents the contraction, as does pre-exposure to cobalt (1 mM) and manganese (1 mM). Both these ions depress saline flow contraction once it is established. Saline flow-dependent contraction changes in a complex manner with temperature. It is greatest in resistance arteries from the pial, ear (skin), and femoral (muscle) segments, moderate to poor in coronary, mesenteric, and renal segments, and absent in the pulmonary segments. A small ear vein adjacent to the ear resistance artery also contracts to saline infusion. Although an explanation based on the washout of a vasodilator metabolite cannot be excluded, we favor the hypothesis that saline flow-induced shear stress of the inner surface of the vessel wall mechanically activates the vascular smooth muscle cells causing an extracellular Ca2(+)-dependent contraction. This response takes place through indomethacin-insensitive calcium-dependent mechanisms in vascular smooth muscle that differ from those associated with commonly studied surface receptors and with stretch.

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Hübner, Alexandra Almeida, Daniel Pecoraro Demarque, Felipe Rebello Lourenço, Catarina Rosado, André Rolim Baby, Irene Satiko Kikuchi et Elfriede Marianne Bacchi. « Phytocompounds Recovered from the Waste of Cabernet Sauvignon (Vitis vinifera L.) Vinification : Cytotoxicity (in Normal and Stressful Conditions) and In Vitro Photoprotection Efficacy in a Sunscreen System ». Cosmetics 10, n^o 1 (21 décembre 2022) : 2. http://dx.doi.org/10.3390/cosmetics10010002.

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We investigated plausible reuse for the dermocosmetic industry of byproducts from the winemaking process of red grapes (Vitis vinifera L. cv. C. Sauvignon) through the evaluation of one extract (grape pomace extract, GPE) and two fractions (one chloroform, GPE-CHF; one ethyl acetate, GPE-EAF). The samples were characterized analytically by liquid chromatography (HPLC) using a NIH 3T3 fibroblast cell culture to verify a cytosafety profile in normal and stressful environment (presence of H2O2), and by using it in a sunscreen system to observe improvements in the in vitro efficacy by diffuse reflectance spectrophotometry with an integrating sphere. The HPLC results for GPE-EAF and GPE-CHF samples with the best profile of syringic and p-coumaric acids, quercetin, and trans-resveratrol were used in the further assays. GPE-EAF and GPE-CHF, both at 30.00 µg/mL, maintained the cell viability in the absence of H2O2 (normal condition). In the sequence, GPE-EAF and GPE-CHF were evaluated against the oxidative stressor H2O2 in NIH 3T3 cells. A sharp drop in viability was only observed for GPE-CHF, and cytotoxicity of GPE-EAF was considered absent even in a hostile environment. Since GPE-EAF previously developed the best results, its potential performance was investigated in a sunscreen system. The in vitro sun protection factor of the phytoderivative-free formulation was 9.0 + 2.5; by adding GPE-EAF at 10.0%, its efficacy was elevated to 15.0 + 2.5. Both samples suffered a negative effect after artificial ultraviolet exposition (500 W/m2); however, the presence of GPE-EAF improved the photostability of the sunscreen system.

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Finkelstein, Yehuda, Yuval Zohar, Yoav P. Talmi et Nelu Laurian. « Study of Toynbee Phenomenon by Combined Intranasopharyngeal and Tympanometric Measurements ». Annals of Otology, Rhinology & ; Laryngology 97, n^o 2 (mars 1988) : 199–206. http://dx.doi.org/10.1177/000348948809700220.

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The Toynbee maneuver, swallowing when the nose is obstructed, leads in most cases to pressure changes in one or both middle ears, resulting in a sensation of fullness. Since first described, many varying and contradictory comments have been reported in the literature concerning the type and amount of pressure changes both in the nasopharynx and in the middle ear. In our study, the pressure changes were determined by catheters placed into the nasopharynx and repeated tympanometric measurements. New information concerning the rapid pressure variations in the nasopharynx and middle ear during deglutition with an obstructed nose was obtained. Typical individual nasopharyngeal pressure change patterns were recorded, ranging from a maximal positive pressure of + 450 to a negative pressure as low as −320 mm H2O.

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Poggere, Giovana Clarice, Beatriz Monte Serrat, Antônio Carlos Vargas Motta, Simone Bittencourt, Maristela Dalpisol et Cleverson Vitório Andreoli. « Lodos de esgoto alcalinizados em solos do estado do Paraná : taxa de aplicação máxima anual e comparação entre métodos para recomendação agrícola ». Engenharia Sanitaria e Ambiental 17, n^o 4 (décembre 2012) : 429–38. http://dx.doi.org/10.1590/s1413-41522012000400010.

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Para o uso agrícola do lodo de esgoto higienizado por processo de estabilização alcalina prolongada (lodo EAP), além de estabelecer limites de aplicação máxima conforme a legislação, é necessário estudar atributos dos lodos e dos solos que favoreçam as metodologias de sua recomendação. Objetivou-se determinar a taxa de aplicação máxima anual (TAMA) de lodo EAP pelo critério de elevação do pH para 20 lodos e solos do estado do Paraná; determinar a influência dos atributos desses solos nos valores da TAMA de lodo EAP; avaliar o uso dos métodos de saturação por bases (V%) e pH referência (SMP), utilizando como padrão o método da incubação. Empregou-se o ensaio de incubação para lodo EAP aplicado ao solo, conforme metodologia oficial. Os resultados indicam que as TAMA de lodo EAP variaram de 10 a >80 Mg.ha-1 para as 20 regionais estudadas; Os atributos químicos (capacidade de troca de cátions, H+Al e carbono) e físico (argila) são os que melhor definem a determinação da TAMA, apresentando relação diretamente proporcional. Os métodos do V% e do pH referência (SMP) para pH H2O 5,5 mostraram-se seguros quanto à recomendação agrícola.

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Corrêa, M. L. T., J. W. V. Mello, A. C. Ribeiro et L. M. Costa. « Métodos de análise de sulfetos em amostras de rochas e sedimentos ». Revista Brasileira de Ciência do Solo 26, n^o 1 (mars 2002) : 103–15. http://dx.doi.org/10.1590/s0100-06832002000100010.

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O presente trabalho foi realizado no período de agosto a dezembro de 1998, com o objetivo de comparar métodos de análise de sulfetos, visando obter uma técnica rápida, exata e reprodutível para avaliar o potencial de drenagem ácida em rochas e sedimentos. As amostras foram submetidas a digestões oxidativas com H2O2 e água régia. Nos extratos, foram determinados o S por gravimetria, por meio do Ba remanescente por espectrofotometria de absorção atômica (EAA), por turbidimetria e por colorimetria. Os teores de Fe e Pb foram determinados por EAA. Nos extratos de H2O2, determinou-se, também, a acidez por titulação com NaOH. A técnica mais indicada para avaliar o teor de sulfetos foi a digestão das amostras com água régia, seguida da determinação indireta do S, por meio do Ba remanescente por EAA. A digestão com H2O2 não foi eficiente para a oxidação total dos sulfetos presentes nas amostras, devendo subestimar o potencial de geração da drenagem ácida em amostras de rochas e sedimentos.

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Singh, Vijay Vikram, Jainendra Jain et Arun Kumar Mishra. « Evaluation of Anticonvulsant and Antioxidant Activity of Senna occidentalis Seeds Extracts ». Journal of Drug Delivery and Therapeutics 9, n^o 2 (15 mars 2019) : 183–87. http://dx.doi.org/10.22270/jddt.v9i2.2400.

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Aim: The aim of present work was to determine the anticonvulsant and antioxidant activity of Senna occidentalis L. ethanolic seed extract by different models. Methods: For evaluation of anticonvulsant activity, Pentylenetetrazole (PTZ) seizure model and Maximal electroshock (MES) seizure model were used. For antioxidant activity, (1, 1-diphenyl - 2-picryl hydrazine (DPPH) and hydrogen peroxide (H2O2) method were used. Results: The finding suggested that the ethanolic extract (EAE) of Senna occidentalis in the dose 400 mg/kg body weight posses potent anticonvulsant activity. The EAE showed anticonvulsant action in dose dependent fashion. It was observed that upon increasing the concentration of extract, it showed reduced absorbance and increased free radical inhibition, and when comparison was made with Ascorbic acid, it showed marked antioxidant property in DPPH as well as H2O2 method. The IC50 of Ascorbic acid and EAE by DPPH method were found to be 14.56 and 14.8 respectively whereas the IC50 of Ascorbic acid and EAE by H2O2 method were found that 14.3and 14.8 respectively. Conclusion: The results of the present study concluded hat the EAE of Senna occidentalis L. possesses significant antioxidant and anticonvulsant activity. The activity was in dose dependent fashion. This study will assist in future research associated with formulation development of seeds of Senna occidentalis L. Keyword: Senna occidentalis L., Anticonvulsant, Antioxidant, DPPH model

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米, 东明. « The Application of Ear-Apex Blood-Letting Therapy for the Treatment of Stye ». Hans Journal of Ophthalmology 04, n^o 04 (2015) : 40–43. http://dx.doi.org/10.12677/hjo.2015.44013.

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Blanco Crivelli, Ximena, María Paz Bonino, Mariana Soledad Sanin, Juan Facundo Petrina, Vilma Noelia Disalvo, Rosana Massa, Elizabeth Miliwebsky, Armando Navarro, Isabel Chinen et Adriana Bentancor. « Potential Zoonotic Pathovars of Diarrheagenic Escherichia coli Detected in Lambs for Human Consumption from Tierra del Fuego, Argentina ». Microorganisms 9, n^o 8 (11 août 2021) : 1710. http://dx.doi.org/10.3390/microorganisms9081710.

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Diarrheagenic Escherichia coli (DEC) pathovars impact childhood health. The southern region of Argentina shows the highest incidence of hemolytic uremic syndrome (HUS) in children of the country. The big island of Tierra del Fuego (TDF) in Argentina registered an incidence of five cases/100,000 inhabitants of HUS in 2019. This work aimed to establish the prevalence of STEC, EPEC, and EAEC in lambs slaughtered in abattoirs from TDF as well as to characterize the phenotypes and the genotypes of the isolated pathogens. The prevalence was 26.6% for stx+, 5.7% for eae+, and 0.27% for aagR+/aaiC+. Twelve STEC isolates were obtained and belonged to the following serotypes: O70:HNT, O81:H21, O81:HNT, O102:H6, O128ab:H2, O174:H8, and O174:HNT. Their genotypic profiles were stx1c (2), stx1c/ehxA (3), stx2b/ehxA (1), stx1c/stx2b (2), and stx1c/stx2/ehxA (4). Six EPEC isolates were obtained and corresponded to five serotypes: O2:H40, O32:H8, O56:H6, O108:H21, and O177:H25. All the EPEC isolates were bfpA- and two were ehxA+. By XbaI-PFGE of 17 isolates, two clusters were identified. By antimicrobial susceptibility tests, 8/12 STEC and 5/6 EPEC were resistant to at least one antibiotic. This work provides new data to understand the ecology of DEC in TDF and confirms that ovine are an important carrier of these pathogens in the region.

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Ann Ellis, E., John R. Guy, Jeffery R. Fitzsimmons et Barbara L. Beck. « Oxidant damage and deterioration of the blood-brain barrier in optic neuritis : A correlative study in the guinea pig by MRI and TEM ». Proceedings, annual meeting, Electron Microscopy Society of America 48, n^o 3 (12 août 1990) : 392–93. http://dx.doi.org/10.1017/s0424820100159503.

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Optic neuritis, a demyelinating autoimmune disease, is usually the initial site of multiple sclerosis (MS). Experimental allergic encephalomyelitis (EAE), the experimental model for MS, is induced by injecting spinal cord emulsion in complete Freund’s Adjuvant into susceptible animals; clinical symptoms of ataxia and hind quarter paralysis develop 8 to 14 days later. Damage to the bloodbrain barrier (BBB) and free radical derived oxidants, including hydrogen peroxide (H2O2), have been implicated in the pathology of EAE and other inflammatory diseases. Cytochemical localization of H2O2 in the optic nerve head of animals with EAE corresponds to areas of extravasation of horseradish peroxidase (HRP) at later stages of EAE. Damage to the BBB is monitored clinically in human cases of MS by magnetic resonance imaging (MRI) of gadolinium-DTPA (Gd-DTPA), contrast agent, leakage. Preliminary studies of EAE with MRI at 4 days post antigen sensitization showed leakage of Gd-DTPA in the optic nerve; light and electron microscopy (TEM) of sections from the same nerve showed substantial inflammation from the optic nerve head to the optic chiasm.

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Horne, Shelley M., et Birgit M. Prüß. « A Wash of Ethyl Acetoacetate Reduces Externally Added Salmonella enterica on Tomatoes ». Antibiotics 11, n^o 8 (21 août 2022) : 1134. http://dx.doi.org/10.3390/antibiotics11081134.

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The continuously high numbers of food-borne disease outbreaks document that current intervention techniques are not yet satisfactory. This study describes a novel wash for tomatoes that can be used as part of the food processing chain and is designed to prevent contamination with serovars of Salmonella enterica. The wash contains ethyl acetoacetate (EAA) at a concentration of 8% in H2O. This wash reduced live bacterial counts (on Salmonella Shigella agar) of externally added S. Newport MDD14 by 2.3 log, counts of S. Typhimurium ATCC19585 by 1.5 log, and counts of S. Typhimurium FSL R6-0020 by 3.4 log. The naturally occurring background flora of the tomatoes was determined on plate count agar. The log reduction by EAA was 2.1. To mimic organic matter in the wash, we added 1% tomato homogenate to the 8% EAA solution. Prior to using the wash, the tomato homogenate was incubated with the EAA for 2 h. In the presence of the tomato homogenate, the log reductions were 2.4 log for S. Newport MDD14 and 3 log for S. Typhimurium FSL R6-0020. It seems like tomato homogenate did not reduce the efficacy of the EAA wash in the two S. enterica serovars tested. We propose the use of EAA as a wash for tomatoes to reduce bacterial counts of S. enterica well as naturally occurring background flora.

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Alper, Cuneyt M., Katherine D. Philp, Juliane M. Banks et William J. Doyle. « Tympanometry Accurately Measures Middle Ear Underpressures in Monkeys ». Annals of Otology, Rhinology & ; Laryngology 112, n^o 10 (octobre 2003) : 877–84. http://dx.doi.org/10.1177/000348940311201009.

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Tympanometry is useful for evaluating middle ear (ME) status, but its accuracy in estimating true ME pressure has been questioned. We evaluated the accuracy of tympanometry in 6 monkeys. Direct application and measurement of ME pressure were achieved with a probe introduced into the mastoid antrum, and tympanometry was done over a large range of applied ME pressures. For all ears, tympanometric pressure was a linear function of applied pressure. At large overpressures, the tympanometric pressure was approximately 40 mm H2O greater than the applied pressure, but there was little error in the measurement for applied underpressures. The measurement error was proportional to the ME pressure multiplied by the ratio of the extant volume displacement of the tympanic membrane to ME volume. These results show that in monkeys, tympanometry provides an accurate, relatively unbiased estimate of ME underpressure and suggest that the measurement error for tympanometry can be predicted for MEs of other species.

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Ligorio, Orsat. « Proto-indo-European ‘eat’ and ‘mouth’ ». Juznoslovenski filolog 75, n^o 2 (2019) : 19–31. http://dx.doi.org/10.2298/jfi1902019l.

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PIE *h1o?-s- (= *h1oh1-s-) ?mouth? is derived from PIE *h1ed- ?to eat?, as an s-stem o-grade postverbal, assuming that *dC yields *?C (= *h1C), which is a well-known phenomenon of the Glottalic Theory.

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Balière, C., A. Rincé, S. Delannoy, P. Fach et M. Gourmelon. « Molecular Profiling of Shiga Toxin-Producing Escherichia coli and Enteropathogenic E. coli Strains Isolated from French Coastal Environments ». Applied and Environmental Microbiology 82, n^o 13 (22 avril 2016) : 3913–27. http://dx.doi.org/10.1128/aem.00271-16.

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ABSTRACTShiga toxin-producingEscherichia coli(STEC) and enteropathogenicE. coli(EPEC) strains may be responsible for food-borne infections in humans. Twenty-eight STEC and 75 EPEC strains previously isolated from French shellfish-harvesting areas and their watersheds and belonging to 68 distinguishable serotypes were characterized in this study. High-throughput real-time PCR was used to search for the presence of 75E. colivirulence-associated gene targets, and genes encoding Shiga toxin (stx) and intimin (eae) were subtyped using PCR tests and DNA sequencing, respectively. The results showed a high level of diversity between strains, with 17 unique virulence gene profiles for STEC and 56 for EPEC. Seven STEC and 15 EPEC strains were found to display a large number or a particular combination of genetic markers of virulence and the presence ofstxand/oreaevariants, suggesting their potential pathogenicity for humans. Among these, an O26:H11stx1aeae-β1 strain was associated with a large number of virulence-associated genes (n= 47), including genes carried on the locus of enterocyte effacement (LEE) or other pathogenicity islands, such as OI-122, OI-71, OI-43/48, OI-50, OI-57, and the high-pathogenicity island (HPI). One O91:H21 STEC strain containing 4stxvariants (stx1a,stx2a,stx2c, andstx2d) was found to possess genes associated with pathogenicity islands OI-122, OI-43/48, and OI-15. Among EPEC strains harboring a large number of virulence genes (n, 34 to 50), eight belonged to serotype O26:H11, O103:H2, O103:H25, O145:H28, O157:H7, or O153:H2.IMPORTANCEThe speciesE. coliincludes a wide variety of strains, some of which may be responsible for severe infections. This study, a molecular risk assessment study ofE. colistrains isolated from the coastal environment, was conducted to evaluate the potential risk for shellfish consumers. This report describes the characterization of virulence gene profiles andstx/eaepolymorphisms ofE. coliisolates and clearly highlights the finding that the majority of strains isolated from coastal environment are potentially weakly pathogenic, while some are likely to be more pathogenic.

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