Search results for "physiologic"
showing 10 items of 2593 documents
Hydrodynamics with spin in bacterial suspensions
2016
We describe a new kind of self-propelling motion of bacteria based on the cooperative action of rotating flagella on the surface of bacteria. Describing the ensemble of rotating flagella in the framework of the hydrodynamics with spin the reciprocal theorem of Stokesian hydrodynamics is generalized accordingly. The velocity of the self-propulsion is expressed in terms of the characteristics of the vector field of flagella orientation and it is shown that unusually high velocities of \textit{Thiovulum majus} bacteria may be explained by the cooperative action of the rotating flagella. The expressions obtained enable us to estimate the torque created by the rotary motors of the bacterium and …
Inactivation of the ftsH gene of Lactobacillus plantarum WCFS1: Effects on growth, stress tolerance, cell surface properties and biofilm formation
2012
FtsH proteins are ubiquitous membrane-bound, ATP-dependent metalloproteases of the AAA family. In eubacteria, FtsH is involved in protein quality control under stress conditions. Lactobacillus plantarum is a widespread lactic acid bacterium that is encountered in several fermented food, including dairy products, vegetables and meat. In the present work the expression of the ftsH gene of L. plantarum was studied by quantitative real time RT-PCR in bacterial cultures subjected to various abiotic stresses. Both oxidative stress and addition of a membrane-fluidizing agent induced ftsH transcription, while a depletion of carbon-source repressed its mRNA level. Mutants deprived of the FtsH protea…
Sympatric and allopatric experimental infections of the planorbid snail Gyraulus chinensis with miracidia of Euparyphium albuferensis (Trematoda: Ech…
2010
AbstractAn experimental infection with echinostomatid miracidia in sympatric or ‘local’ vs. allopatric or ‘away’ snail combinations, as a model to examine parasite compatibility, was carried out. We employedEuparyphium albuferensismiracidia to infectGyraulus chinensissnails, from three different natural parks: Albufera (Valencia, Spain); the Ebro Delta (Tarragona, Spain) and Coto de Doñana (Huelva, Spain). Insignificant differences between the three snail strains were noted for the infection rate and the rhythm of daily cercarial production. However, a significantly higher total cercarial production per snail, patent period and life span were observed in local snails. The different infectio…
Biological invasion and parasitism: invaders do not suffer from physiological alterations of the acanthocephalan Pomphorhynchus laevis.
2009
SUMMARYBiological invasions expose parasites to new invasive hosts in addition to their local hosts. However, local parasites are often less successful in infecting and exploiting their new hosts. This may have major consequences for the competitive ability of hosts, and finally on the fate of the parasite-host community. In Burgundy (Eastern France), the acanthocephalan parasite,Pomphorhynchus laevis, infects 2 amphipod species living in sympatry: the nativeGammarus pulexand the invasiveGammarus roeseli. WhileP. laevisaffects the behaviour and the immunity ofG. pulex,G. roeseliseems unaffected by the infection. In this study, we examined in detail the ability of the parasite to affect the …
Adaptive radiation along a thermal gradient: preliminary results of habitat use and respiration rate divergence among whitefish morphs.
2014
Adaptive radiation is considered an important mechanism for the development of new species, but very little is known about the role of thermal adaptation during this process. Such adaptation should be especially important in poikilothermic animals that are often subjected to pronounced seasonal temperature variation that directly affects metabolic function. We conducted a preliminary study of individual lifetime thermal habitat use and respiration rates of four whitefish (Coregonus lavaretus (L.)) morphs (two pelagic, one littoral and one profundal) using stable carbon and oxygen isotope values of otolith carbonate. These morphs, two of which utilized pelagic habitats, one littoral and one …
Use of Different Food Classification Systems to Assess the Association between Ultra-Processed Food Consumption and Cardiometabolic Health in an Elde…
2021
The PREDIMED-Plus trial was supported by the European Research Council (Advanced Research grant 2014–2019; agreement #340918; granted to M.Á.M.-G.); the official Spanish institutions for funding scientific biomedical research, CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN) and Instituto de Salud Carlos III (ISCIII) through the Fondo de Investigación para la Salud (FIS) which is co-funded by the European Regional Development Fund (coordinated FIS projects led by J.S-S. and J.V., including the following projects: PI13/00673, PI13/00492, PI13/00272, PI13/01123, PI13/00462, PI13/00233, PI13/02184, PI13/00728, PI13/01090, PI13/01056, PI14/01722, PI14/00636, PI14/00618, PI14/00696, PI…
The Effect of Physical Activity and High Body Mass Index on Health-Related Quality of Life in Individuals with Metabolic Syndrome
2020
© 2020 by the authors.
Reversible effect of MR and ELF magnetic fields (0.5 T and 0.5 mT) on human lymphocyte activation patterns.
2006
Purpose: The aim of this study was to investigate the effects of magnetic fields (MF) of different intensity generated by a magnetic resonance (MR) unit (0.5 Tesla) and a double cylindrical coil (0.5 mTesla) on human CD4+ T cell lines. Materials and methods: CD4+ T cells were exposed for two hours under isothermal conditions (37 ± 0.5°C) to the above mentioned MF; a control group was provided for each exposed sample. After exposure, the samples were analysed in the laboratory for the following endpoints: Release of cytokines, expression of surface markers, cell proliferation and levels of cytosolic free-calcium. Results: Exposure to MF for 2 h and subsequent in vitro stimulation in the pres…
Wheat Amylase Trypsin Inhibitors as Nutritional Activators of Innate Immunity
2015
While the central role of an adaptive, T cell-mediated immune response to certain gluten peptides in celiac disease is well established, the innate immune response to wheat proteins remains less well defined. We identified wheat amylase trypsin inhibitors (ATIs), but not gluten, as major stimulators of innate immune cells (dendritic cells > macrophages > monocytes), while intestinal epithelial cells were nonresponsive. ATIs bind to and activate the CD14-MD2 toll-like receptor 4 (TLR4) complex. This activation occurs both in vitro and in vivo after oral ingestion of purified ATIs or gluten, which is usually enriched in ATIs. Wheat ATIs represent a family of up to 17 proteins with molec…
HIV-1 Adaptation to Antigen Processing Results in Population-Level Immune Evasion and Affects Subtype Diversification
2014
Summary The recent HIV-1 vaccine failures highlight the need to better understand virus-host interactions. One key question is why CD8+ T cell responses to two HIV-Gag regions are uniquely associated with delayed disease progression only in patients expressing a few rare HLA class I variants when these regions encode epitopes presented by ∼30 more common HLA variants. By combining epitope processing and computational analyses of the two HIV subtypes responsible for ∼60% of worldwide infections, we identified a hitherto unrecognized adaptation to the antigen-processing machinery through substitutions at subtype-specific motifs. Multiple HLA variants presenting epitopes situated next to a giv…