Consulta: subjectFacets:"Chemotaxis"
Registros recuperados: 8
Data/hora: 04/06/2024 01:27:36

Bothrops snake venoms and their isolated toxins, an L-amino acid oxidase and a serine protease, modulate human complement system pathways
Provedor de dados: Journal of Venomous Animals and Toxins Including Tropical Diseases
Autores: Ayres,Lorena Rocha; Récio,Alex dos Reis; Burin,Sandra Mara; Pereira,Juliana Campos; Martins,Andrea Casella; Sampaio,Suely Vilela; Castro,Fabíola Attié de; Pereira-Crott,Luciana Simon.
Background Activation of the complement system plays an important role in the regulation of immune and inflammatory reactions, and contributes to inflammatory responses triggered by envenomation provoked byBothrops snakes. The present study aimed to assess whether Bothrops jararacussuand Bothrops pirajai crude venoms and their isolated toxins, namely serine protease (BjussuSP-I) and L-amino acid oxidase (BpirLAAO-I), modulate human complement system pathways.Methods Lyophilized venom and toxin samples solubilized in phosphate buffered saline were diluted in appropriate buffers to evaluate their hemolytic activity on the alternative and classical pathways of the complement system. Venom- and toxin-treated normal human serum was added to the erythrocyte...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bothrops jararacussu; Bothrops pirajai; Chemotaxis; Complement system; Kinetic microassay; L-amino acid oxidase; Serine protease; Snake venom.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992015000100336

Selective attraction of marine bacterivorous nematodes to their bacterial food
Provedor de dados: Open Marine Archive
Autores: Moens, T.; Verbeeck, L.; de Mayer, A.; Swings, J.; Vincx, M.
This paper explores the role of selective attraction to food in determining the spatial (micro)distribution of closely related nematode species. The attractiveness of 3 different bacterial strains to 4 species of Monhysteridae, &lt;i&gt;Diplolaimelloides meyli, Diplolaimella dievengatensis, Monhystera&lt;/i&gt; sp. and &lt;i&gt;Geomonhystera disjuncta&lt;/i&gt;, was studied in a multiple choice design. In our study area, the 4 nematode species considered are associated with &lt;i&gt;Spartina anglica&lt;/i&gt; detritus decay and have partially overlapping microhabitat preferences. As they all belong to the same feeding guild, they are potential competitors for food. Each of the 4 nematode species was attracted to the bacterial strain B1, but important...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chemotaxis; Recruitment; Taxis; Bacteria; Diplolaimella dievengatensis; Diplolaimelloides meyli; Geomonhystera disjuncta; Nematoda [Nematodes]; Spartina anglica [common cord-grass].
Ano: 1999
URL: http://www.vliz.be/imisdocs/publications/273317.pdf

tlpA gene expression is required for arginine and bicarbonate chemotaxis in Helicobacter pylori
Provedor de dados: Biological Research
Autores: Cerda,Oscar A; Núñez-Villena,Felipe; Soto,Sarita E; Ugalde,José Manuel; López-Solís,Remigio; Toledo,Héctor.
About half of the human population is infected with Helicobacter pylori, a bacterium causing gastritis, peptic ulcer and progression to gastric cancer. Chemotaxis and flagellar motility are required for colonization and persistence of H. pylori in the gastric mucus layer. It is not completely clear which chemical gradients are used by H. pylori to maintain its position. TlpA, a chemotaxis receptor for arginine/ bicarbonate, has been identified. This study aimed to find out whether tlpA gene expression is required for the chemotactic response to arginine/bicarbonate. Wild-type motile H. pylori ATCC 700392 and H. pylori ATCC 43504, a strain having an interrupted tlpA gene, were used. Also, a tlpA-knockout mutant of H. pylori 700392 (H. pylori 700-tlpA::cat)...
Tipo: Journal article
Palavras-chave: TlpA; Chemotaxis; Helicobacter pylori; Arginine; Bicarbonate.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602011000300009

Overview on chemotaxis and acid resistance in Helicobacter pylori
Provedor de dados: Biological Research
Autores: VALENZUELA,MANUEL; CERDA,OSCAR; TOLEDO,HÉCTOR.
Tipo: Journal article
Palavras-chave: Helicobacter pylori; Acid tolerance response; Chemotaxis; Urease.
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602003000300014

Comparison of chemical constituents of Chamomilla recutita (L.) rauschert essential oil and its anti-chemotactic activity
Provedor de dados: Brazilian Archives of Biology and Technology
Autores: Presibella,Mayra Marinho; Villas-Bôas,Larissa De Biaggi; Belletti,Klézia Morais da Silva; Santos,Cid Aimbiré de Moraes; Weffort-Santos,Almeriane Maria.
Several essential oil samples from dried flower-heads of Chamomilla recutita (L.) Rauschert, grown and commercially available around Curitiba metropolitan area, South of Brazil, were analyzed by GC-MS and the chemical constituents were compared with an Egyptian sample obtained under similar conditions and used as a control. The local grown herbs showed levels of essential oil below the standards recommended by the Brazilian Pharmacopoeia. Also, differences in their composition as well as in the quantity of several components were found such as the unexpected inversion of the relative constitution of the A and B alpha-bisabolol oxides. Of particular interest was the striking effect of the chamomile extracts upon human leukocyte chemotaxis, a biological...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chamomilla recutita; Asteraceae; Essential oil; Chemotaxis; Bisabolol oxide.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000600005

Chemotaxis and chemical defenses in seaweed susceptibility to herbivory
Provedor de dados: Brazilian Journal of Biology
Autores: PEREIRA,R. C.; DONATO,R.; TEIXEIRA,V. L.; CAVALCANTI,D. N.
Recent studies have show that small marine herbivores with limited mobility (mesograzers) often feed on macroalgae chemically defended against fishes or sea-urchins. In order to verify the involved mechanisms of chemotaxis or chemical defense into this process in Brazilian littoral, two species of brown alga Dictyota menstrualis and Dictyota mertensii were studied against the limited mobility herbivores, the amphipod Parhyale hawaiensis and the crab Pachygrapsus transversus. These two species were studied in order to verify the action of their crude extracts in the defense and chemotaxis processes related to limited mobility of these herbivores. Feeding preference assays revealed that P. hawaiensis do not eaten these Dictyota species. P. transversus do not...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Seaweed; Chemical defense; Chemotaxis; Feeding.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0034-71082000000300005

Regenerated extracellular NH4+ affects the motile chemosensory responses of batch-cultured Oxyrrhis marina
Provedor de dados: Brazilian Journal of Microbiology
Autores: Martel,Claire M.
Regenerated extracellular NH4+in laboratory batch-cultures of the heterotrophic marine microzooplankter Oxyrrhis marina affects the strength and consistency of chemotaxes elicited by synthetic and biogenic chemoattractants. The ecological relevance of experiments with batch-cultured O. marina and limitations of the microcapillary assay for the study of chemosensory behaviours are discussed.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chemosensory; Chemotaxis; Chemotaxes; Oxyrrhis marina.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822010000200010

Biodegradation of naphthalene and anthracene by chemo-tactically active rhizobacteria of populus deltoides
Provedor de dados: Brazilian Journal of Microbiology
Autores: Bisht,Sandeep; Pandey,Piyush; Sood,Anchal; Sharma,Shivesh; Bisht,N. S.
Several naphthalene and anthracene degrading bacteria were isolated from rhizosphere of Populus deltoides, which were growing in non-contaminated soil. Among these, four isolates, i.e. Kurthia sp., Micrococcus varians, Deinococcus radiodurans and Bacillus circulans utilized chrysene, benzene, toluene and xylene, in addition to anthracene and naphthalene. Kurthia sp and B. circulans showed positive chemotactic response for naphthalene and anthracene. The mean growth rate constant (K) of isolates were found to increase with successive increase in substrate concentration (0.5 to 1.0 mg/50ml). B. circulans SBA12 and Kurthia SBA4 degraded 87.5% and 86.6% of anthracene while, Kurthia sp. SBA4, B. circulans SBA12, and M. varians SBA8 degraded 85.3 %, 95.8 % and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biodegradation; Chemotaxis; Anthracene; Naphthalene.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822010000400011