Presence of Porphyromonas and Prevotella species in the oral microflora of cattle with periodontitis

Abstratc: Bovine periodontitis is a progressive purulent infectious process associated with the presence of strictly and facultative anaerobic subgingival biofilm and epidemiologically related to soil management in large geographic areas of Brazil. This study aimed to detect species of the genera Porphyromonas and Prevotella, which occurr in periodontal pockets of cattle with lesions deeper than 5mm (n=26) and in gingival sulcus of animals considered periodontally healthy (n=25). Presence of the microorganisms was evaluated by independent-culture medium diagnostic method, using polymerase chain reaction (PCR) with specific primers of Porphyromonas asaccharolytica, P. endodontalis, P. gingivalis, P. gulae, Prevotella buccae, P. intermedia, P. loescheii, P. melaninogenica, P. nigrescens, P. oralis and P. tannerae. The species P. endodontalis (80.7%), P. melaninogenica (73.1%) and P. intermedia (61.5%) were the most predominant in samples of cattle with periodontitis. Regarding non-injured gingival sulcus of cattle, P. endodontalis (40%) and P. loeschei (40%) prevailed. Porphyromonas gingivalis, P. gulae and Prevotella tannerae were not detected in the 51 samples studied. Data evaluation by T test, enabled to verify that ocorrence of Porphyromonas asaccharolytica (p=0.000003), P. endodontalis (p=0.0023), Prevotella buccae (p=0.0017), P. intermedia (p=0.0020), P. melaninogenica (p=0.00006) and P. oralis (p=0.0028) is correlated with bovine periodontitis.

A família Lemnaceae Gray no Pantanal (Mato Grosso e Mato Grosso do Sul), Brasil

Realizou-se o levantamento de plantas aquáticas da família Lemnaceae no Pantanal do Mato Grosso e Mato Grosso do Sul, a qual está representada por nove espécies, distribuídas em quatro gêneros. Das espécies encontradas somente Wolffia brasiliensis Wedd. e Lemna valdiviana Phil. haviam sido registradas no Pantanal. As demais espécies são Spirodela intermedia W. Koch, Lemna aequinoctialis Welw., L. minuta Kunth, in Humb., Bonp. & Kunth, Wolffiella welwitschii (Hegelm.) Monod, W. lingulata (Hegelm.) Hegelm., W. oblonga (Phil.) Hegelm. e Wolffia columbiana H. Karst. As Lemnaceae ocorrem em todas as 10 sub-regiões do Pantanal, com o maior número de espécies na sub-região do Nabileque, de solos mais férteis.

Morfologia externa e interna das folhas vegetativas, esporofilos e esporângios de espécies de Huperzia Bernh. (Lycopodiaceae - Pteridophyta) do Brasil

Lycopodiaceae está inserida em Lycopsida, cuja autapomorfia é a presença de folhas microfilas. Foram estudadas 10 espécies, sete delas endêmicas do Brasil: Huperzia christii (Silveira) Holub, H. friburgensis (Nessel) B. Øllg., H. hemleri (Nessel) B. Øllg., H. intermedia Trevis., H. reflexa (Lam.) Trevis. e H. treitubensis (Silveira) B. Øllg., estas terrestres; H. fontinaloides (Spring) Trevis., H. heterocarpon (Fée) Holub, H. hexasticha B. Øllg. & P.G. Windisch e H. quadrifariata (Bory) Rothm., estas epífitas. As características anatômicas encontradas, que podem ser adaptativas ao ambiente com escassez hídrica são a presença de células epidérmicas com paredes anticlinais sinuosas, invaginações na face interna da parede periclinal externa das células epidérmicas e folhas anfiestomáticas. As espécies estudadas foram reunidas em dois grupos, corroborando classificações existentes. Os grupos foram definidos com base nas seguintes características: a filotaxia, se helicoidal ou oposta, a posição das folhas em relação ao caule, se reflexas ou adpressas, e o número de camadas de células do esporângio, se três ou quatro. Foi elaborada uma chave de identificação.

Modulation of Signaling Molecules by Human Leucocyte Antigen B27; Special Reference to STAT1

Reactive arthritis (ReA) is an inflammatory joint disease, which belongs to the group of Spondyloarthritis (SpA). It may occur after infections with certain gram-negative bacteria such as Salmonella and Yersinia. SpAs are strongly associated with the human leucocyte antigen (HLA)-B27. Despite active research, the mechanism by which HLA-B27 causes disease susceptibility is still unknown. However, HLA-B27 has a tendency to misfold during assembly. It is possible that the misfolding of HLA-B27 could alter signaling pathways and/or molecules involved in inflammatory response in cells. We have earlier discovered that in HLA-B27-positive cells the interaction between the host and causative bacteria is disturbed. Our recent studies indicate that the expression of HLA-B27 may alter certain signaling molecules by disturbing their activation. The aim of this study was to investigate whether the expression of HLA-B27 disturbs the signaling molecules, especially the phosphorylation of transcription factor STAT1. STAT1 is an important mediator of inflammatory responses. Our results show that the phosphorylation of the STAT1 is significantly altered in HLA-B27-expressing U937 monocytic cells compared with control cells. STAT1 tyrosine 701 is more strongly phosphorylated in HLAB27- expressing cells; whereas the phosphorylation of STAT1 serine 727 is prolonged. Phosphorylation of STAT1 was discovered to be dependent on protein kinase PKR. Furthermore, we found out that the expression of posttranscriptional gene regulator HuR was altered in HLA-B27-expressing cells. We also detected that HLA-B27-positive cells secrete more interleukin 6, which is an important mediator of inflammation. These results help to understand how HLA-B27 may confer susceptibility to SpAs.

The use of filter paper plasticized with polyvinyl alcohol-glutaraldehyde in ELISA

F1-antigen purified from Yersinia pestis was covalently linked to 5-mm diameter filter paper discs plasticized with polyvinyl alcohol-glutaraldehyde. These discs were used both for ELISA and dot-ELISA for the detection of anti-F1 IgG in rabbits. The best conditions were achieved using 1.25 µg of F1 antigen/disc, 3% w/v skim milk in PBS as blocking agent, anti-IgG peroxidase conjugate diluted 12,000 times, and serum from rabbits immunized or not against Y. pestis, diluted 6,400 times. The absorbance values obtained from the comparative study between this procedure and conventional ELISA were not significantly different but the low cost of the reagents employed in ELISA using the filter paper discs plasticized with polyvinyl alcohol-glutaraldehyde makes this method economically attractive.

Extracellular matrix molecules as targets for brown spider venom toxins

Loxoscelism, the term used to describe lesions and clinical manifestations induced by brown spider's venom (Loxosceles genus), has attracted much attention over the last years. Brown spider bites have been reported to cause a local and acute inflammatory reaction that may evolve to dermonecrosis (a hallmark of envenomation) and hemorrhage at the bite site, besides systemic manifestations such as thrombocytopenia, disseminated intravascular coagulation, hemolysis, and renal failure. The molecular mechanisms by which Loxosceles venoms induce injury are currently under investigation. In this review, we focused on the latest reports describing the biological and physiopathological aspects of loxoscelism, with reference mainly to the proteases recently described as metalloproteases and serine proteases, as well as on the proteolytic effects triggered by L. intermedia venom upon extracellular matrix constituents such as fibronectin, fibrinogen, entactin and heparan sulfate proteoglycan, besides the disruptive activity of the venom on Engelbreth-Holm-Swarm basement membranes. Degradation of these extracellular matrix molecules and the observed disruption of basement membranes could be related to deleterious activities of the venom such as loss of vessel and glomerular integrity and spreading of the venom toxins to underlying tissues.

Polysiloxane/PVA-glutaraldehyde hybrid composite as solid phase for immunodetections by ELISA

We developed an efficient method to prepare a hybrid inorganic-organic composite based on polyvinyl alcohol (PVA) and polysiloxane using the sol-gel disc technique. Antigen obtained from Yersinia pestis was covalently immobilized onto these discs with glutaraldehyde and used as solid phase in ELISA for antibody detection in serum of rabbits experimentally immunized with plague. Using 1.25 µg antigen per disc, a peroxidase conjugate dilution of 1:4,000 and a serum dilution of 1:200 were adequate for the establishment of the procedure. These values are similar to those used for PVA-glutaraldehyde discs, plasticized filter paper discs and the polyaniline-Dacron composite discs. This procedure is comparable to that which utilizes the adsorption of the antigen to conventional PVC plates, with the amount of antigen being one fourth that employed in conventional PVC plates (5 µg/well). In addition to the performance of the polysiloxane/PVA-glutaraldehyde disc as a matrix for immunodetection, its easy synthesis and low cost are additional advantages for commercial application.

Interference of heating on the antimicrobial activity and chemical composition of Origanum vulgare L. (Lamiaceae) essential oil

Origanum vulgare L. (oregano), Lamiaceae, essential oil has a variety of biological properties and its antimicrobial activity has received a renewed interest for use in food conservation. The aim of this study was to evaluate the interference of heating on the antimicrobial activity and chemical composition of O. vulgare essential oil. The antimicrobial activity of the essential oil kept at room temperature and exposed to different heating temperatures (60, 80, 100 and 120 °C during 1 hour) was evaluated by observing antimicrobial effectiveness at absolute concentration and determining MIC values by the solid medium diffusion procedure. The essential oil chemical composition analysis was performed by GC-MS. O. vulgare essential oil showed interesting antimicrobial activity on all assayed microbial strains (Candida albicans, C.krusei, C. tropicalis, Bacillus cereus, Escherichia coli, Staphylococcus aureus, Yersinia enterocolitica, Salmonella enterica, Serratia marcencens), noted by large growth inhibition zones (30-42 mm). Heating treatment showed no significant interference (p < 0.05) on the essential oil antimicrobial activity, noted by the development of microbial growth inhibition zones with similar or close diameters when evaluating the essential oil kept at room temperature and after exposure to different thermal treatments. MIC values oscillated between 10and 40 µL.mL-1 (20µL.mL-1 for most strains). However, no significant difference (p < 0.05) was noted among the MIC values found for the essential oil aliquots exposed to different temperatures. Moreover, heating did not significantly (p < 0.05) affect the chemical composition of O. vulgare essential oil. Monoterpenes, terpenic compounds and sesquiterpenes were found in the essential oil, with carvacrol (68.06-70.27%) and p-cymene (12.85-15.81%) being the compounds found in the highest amounts. These results showed the thermal stability and intense antimicrobial properties of O. vulgare essential oil and support its possible concomitant use with heating temperatures in order to reach microbial safety in foods.

Atividade antimicrobiana e antioxidante do óleo essencial de ho-sho (Cinnamomum camphora Ness e Eberm Var. Linaloolifera fujita)

Este trabalho teve como objetivo determinar a atividade antimicrobiana e antioxidante do óleo essencial de Ho-Sho. O principal componente do óleo essencial obtido a partir de folhas da planta submetidas ao processo de hidrodestilação foi o linalol (80 a 95% m/m). O óleo essencial mostrou atividade antimicrobiana para todos os microrganismos testados, com exceção de Pseudomonas aeruginosa. A maior atividade antimicrobiana do óleo essencial sobre as bactérias testadas foi observada sobre Xanthomonas campestris (33,0 mm) e a menor sobre Yersinia enterocolitica (10,5 mm). Para a concentração inibitória mínima (CIM), observou-se que todos os microrganismos apresentaram-se susceptíveis ao óleo essencial de Ho-Sho. A variação das CIM para as bactérias Gram-positivas foi de 1,00 mg.mL-1 (Streptococcus mutans) a 1,75 mg.mL-1 (Staphylococcus epidermidis). Já a variação das CIM para as bactérias Gram-negativas foi de 0,625 mg.mL-1 (Citrobacter freundii) a 2,50 mg.mL-1 (Shigella flexneri). Os resultados obtidos na determinação da atividade antioxidante do óleo essencial demonstram que o percentual antioxidante aumenta proporcionalmente à concentração de óleo essencial adicionado, atingindo o valor máximo de 97,49% de atividade antioxidante para a concentração de 50000 μg.mL-1.

Armazenamento de sementes de orquídeas

Sementes de dezesseis espécies de orquídeas foram armazenadas a 5ºC por até 42 meses, sendo verificada a viabilidade pelo teste de tetrazólio e de germinação. Houve perda da viabilidade conforme incremento no período de armazenamento. Por doze meses, a maioria das espécies estocadas a 5ºC, em dessecador com umidade relativa de ± 6% de conteúdo de água, conservou a viabilidade próxima aos 100%, com exceção da Cattleya labiata que apresentou queda de cerca de 50% da viabilidade inicial. Cattleya intermedia, Encyclia pygmaea, E. odorantissima, Grobya sp., Oncidium flexuosum, Oncidium pumilum e um híbrido natural, Laeliocattleya conservaram, em geladeira, a viabilidade das sementes acima de 90%, por até 24 meses. Para Cattleya intermédia, realizou-se armazenamento de sementes em tubos de polipropileno a 5, -18 e a 25ºC, em dessecador ou condições ambientais sem controle de umidade. Em condições de laboratório houve perda quase total da viabilidade das sementes. A estocagem em geladeira a 5ºC ou em "freezer" a - 18ºC fornece condições adequadas para conservar a viabilidade de sementes de orquídeas. Com essa mesma espécie, as sementes foram armazenadas a -18ºC durante 24 semanas, sendo testada semanalmente sua viabilidade. Para tais avaliações, as sementes eram transferidas diretamente de -18ºC para temperatura ambiente de laboratório (25ºC) ou indiretamente, por uma hora a 5ºC, depois para temperatura ambiente por uma hora. A transferência indireta foi mais eficiente na conservação da viabilidade.

Observatorio de movilidad boletín de mantenimiento vial. N. 3

Gestión del conocimiento

Informe de seguimiento No. 26 Construcción Troncal Carrera 10 - TransMilenio Fase III

Gestión del conocimiento

Informe de seguimiento No.29. Construcción Troncal de TransMilenio Fase III, Grupo 5

Gestión del conocimiento

Étude des gènes d'Actinobacillus pleuropneumoniae exprimés en conditions d'infection

Actinobacillus pleuropneumoniae est l’agent étiologique de la pleuropneumonie porcine. La bactérie se transmet par voies aériennes et contacts directs. Plusieurs facteurs de virulence ont été identifiés, nommément les polysaccharides capsulaires, les lipopolysaccharide, les exotoxines ApxI à IV et de nombreux mécanismes d’acquisition du fer. Aucun vaccin efficace contre tous les sérotypes de la bactérie n’a encore été élaboré. Afin de mieux comprendre de quelle façon A. pleuropneumoniae régule la transcription de ses nombreux facteurs de virulence et de découvrir de nouvelles cibles potentielles pour l’élaboration de vaccins efficaces, le profil transcriptomique de la bactérie a été étudié dans des conditions simulant l’infection ainsi qu’à la suite d’une infection naturelle aiguë chez l’animal. Des biopuces de première et de seconde génération (AppChip1 et AppChip2) comportant respectivement 2025 cadres de lecture ouverts (ORF) de la version préliminaire du génome d’A. pleuropneumoniae sérotype 5b souche L20 et 2033 ORF de la version finale annotée du même génome ont été utilisées. Dans un premier temps, des expériences réalisées dans des conditions de concentration restreinte en fer ont permis d’identifier 210 gènes différentiellement exprimés, dont 92 étaient surexprimés. Plusieurs nouveaux mécanismes d’acquisition du fer ont pu être identifiés, incluant un système homologue au système YfeABCD de Yersinia pestis, impliqué dans l’acquisition du fer chélaté, ainsi que des gènes homologues aux composantes du système HmbR de Neisseria meningitidis impliqué dans l’acquisition du fer à partir de l’hémoglobine. Dans des conditions de culture permettant la formation de biofilms, les gènes tadC et tadD d’un opéron tad (« tight adherence locus ») putatif, les gènes pgaBC impliqués dans la synthèse d’un polysaccharide de la matrice du biofilm ainsi que deux gènes présentant de fortes homologies avec un gène codant pour l’adhésine auto-transporteur Hsf retrouvée chez Haemophilus influenzae ont montré une surexpression significative. Plusieurs de ces gènes ont également été retrouvés lors d’expériences réalisées avec des cellules épithéliales d’origine pulmonaire en culture, qui ont permis d’identifier 170 gènes différentiellement exprimés après la croissance planctonique au-dessus des cellules, et 131 autres suite à l’adhésion à ces cellules. Parmis les gènes surexprimés, les gènes tadB et rcpA de l’opéron tad putatif, les gènes pgaBC ainsi que le gène codant pour l’homologue d’Hsf ont été retrouvés. En présence de liquide de lavage broncho-alvéolaire (BALF), 156 gènes ont montré un profil d’expression modifié, et le gène apxIVA, identifié comme étant surexprimé, a pu être détecté pour la première fois dans des conditions de croissance in vitro. Finalement, des expériences visant à déterminer les gènes utilisés directement chez l’animal en phase aiguë de la pleuropneumonie porcine ont permis d’identifier 150 gènes qui étaient différentiellement exprimés. En plus d’identifier des gènes d’un possible opéron codant pour un fimbriae de type IV, 3 des 72 gènes surexprimés sont conservés chez tous les sérotypes d’A. pleuropneumoniae et codent pour des protéines ou lipoprotéines de surface. Nos expériences ont permis d’identifier plusieurs nouveaux facteurs de virulence potentiels chez A. pleuropneumoniae ainsi que plusieurs nouvelles cibles potentielles pour l’élaboration de vaccins efficaces contre tous les sérotypes.

Scénographies mémorielles et figurations médiatiques de la guerre d’Algérie

Cette thèse montre comment fonctionnent et se déploient, au sein des œuvres littéraires, filmiques et webfilmiques, des scénographies mémorielles et des figurations médiatiques de la guerre d’Algérie. Empruntant sa méthodologie à la sociocritique des textes et aux études intermédiales, l’étude porte sur la manière dont le souvenir de l’évènement se confond avec celle de le relater. Elle examine le rôle du médium qui donne une forme, une matérialité, un dispositif, un type de reconnaissance institutionnelle aux représentations de la guerre et de la mémoire, contribuant aussi à former, modeler le souvenir en le rendant perceptible et intelligible. Comment les groupes de mémoire de la guerre d’Algérie, (harkis, immigration algérienne, pieds-noirs) vivent-ils – toutes proportions et différences gardées – leur rapport au passé à partir du présent ? Leurs mémoires, médiées par les vecteurs culturels (cinéma, littérature, etc.), se disent à partir de sites d’énonciations plurielles dont les espaces (topographies) et les temps (chronographies) sont communs. Elles s’approprient le souvenir de façon similaire, par les scènes narratives du procès, de la rencontre ou du retour construites par le texte littéraire ou filmique. La première partie interroge les rapports entre histoire et mémoire ; en France, leurs conceptions et pratiques, se heurtent à une nouvelle économie mémorielle dans laquelle des groupes de mémoire de la guerre d’Algérie réclament que leur histoire soit reconnue et enseignée. Appuyée par une périodisation de la production gigantesque des cinquante dernières années et par une revue critique de la recherche internationale menée à ce sujet, cette réflexion prend acte de la dispute post-coloniale française et considère l’auteur porteur de mémoire de la guerre d’Algérie pour son exemplarité en tant que témoin post-colonial. Les deuxième, troisième et quatrième parties de cette thèse déplient quant à elles, la scénographie mémorielle spécifique à trois auteurs, tout en la mettant en relation avec d’autres œuvres de genre et médium très différents. Le premier corpus est composé de : Moze de Zahia Rahmani, du tryptique de Mehdi Charef (À-bras-le-cœur, 1962. Le dernier voyage, Cartouches gauloises) et d’Exils de Tony Gatlif. À ces titres s’ajoutent des œuvres qui marquent une série, ensemble aux contours flous auxquels ils se rattachent et qui permettent de mettre à la fois en perspective le commun entretenu entre la série et l’œuvre de l’un des trois auteurs, et la manière dont l’auteur, Rahmani, Charef ou Gatlif s’en distingue de façon significative. Enfin, un troisième type d’œuvres intervient dans l’analyse comme contrepoint souvent paradoxal de cette série.