Search results for "nema"

Plastic and micro-evolutionary responses of a nematode to the host immune environment

2017

9 pages; International audience; Parasitic organisms have to cope with the defences deployed by their hosts and this can be achieved adopting immune evasion strategies or optimal life history traits according to the prevailing pattern of immune-mediated mortality. Parasites often encounter variable immune environments both within and between hosts, promoting the evolution of plastic strategies instead of fixed responses. Here, we explored the plasticity and micro-evolutionary responses of immunomodulatory mechanisms and life history traits to the immune environment provided by the host, using the parasitic nematode Heligmosomoides polygyrus. To test if the parasite responds plastically to t…

Reanalysis of Chinese Treponema pallidum samples: all Chinese samples cluster with SS14-like group of syphilis-causing treponemes

2018

[Objective]: Treponema pallidum subsp. pallidum (TPA) is the causative agent of syphilis. Genetic analyses of TPA reference strains and human clinical isolates have revealed two genetically distinct groups of syphilis-causing treponemes, called Nichols-like and SS14-like groups. So far, no genetic intermediates, i.e. strains containing a mixed pattern of Nichols-like and SS14-like genomic sequences, have been identifed. Recently, Sun et al. (Oncotarget 2016. https://doi. org/10.18632/oncotarget.10154) described a new “phylogenetic group” (called Lineage 2) among Chinese TPA strains. This lineage exhibited a “mosaic genomic structure” of Nichols-like and SS14-like lineages.

Tooth abnormalities in individuals with unilateral alveolar clefts : a comparison between sides using cone-beam computed tomography

2017

Background: Tooth abnormalities are most often present in individuals with oral clefts than general population, and lead to a long-term impact on facial anatomy and self-esteem. The purpose of this study was to compare the proportion of dental anomalies between the cleft side and non-cleft side in individuals with non-syndromic unilateral alveolar clefts (AC). Material and Methods: Twenty cone beam computed tomography (CBCT) scans were converted into threedimensional (3D) virtual models. The dental anomalies considered were: tooth agenesis; supernumerary teeth; giroversion; and microdontia. Statistical analysis was performed using the McNemar?s test and Fisher?s exact test ( p < 0.05). Resu…

Starter cultures as biocontrol strategy to prevent Brettanomyces bruxellensis proliferation in wine

2017

Brettanomyces bruxellensis is a common and significant wine spoilage microorganism. B. bruxellensis strains generally detain the molecular basis to produce compounds that are detrimental for the organoleptic quality of the wine, including some classes of volatile phenols that derive from the sequential bioconversion of specific hydroxycinnamic acids such as ferulate and p-coumarate. Although B. bruxellensis can be detected at any stage of the winemaking process, it is typically isolated at the end of the alcoholic fermentation (AF), before the staring of the spontaneous malolactic fermentation (MLF) or during barrel aging. For this reason, the endemic diffusion of B. bruxellensis leads to c…

Dogs and Guinea worm eradication

2016

After 30 years of control campaigns, guinea worm faces eradication. However, dogs are expected to thwart the eradication of dracunculiasis as they act as alternative hosts of the worm. The health community un doubtedly have to recognise the success of the Guinea Worm Eradication Program (GWEP), although some flaws cannot be overlooked. One of the most essential points when trying to achieve the control of parasitic infections is to determine the role of reservoirs that could maintain the disease. Erroneously, dogs are likely to have been ignored as reservoirs of Dracunculus medinensis so far. I fi nd it hard to believe that a parasite that has always been considered specific to humans is ab…

The Guinea Worm: A Zoonotic Parasite of Dogs

2017

Chemical Transfers Occurring Through Oenococcus oeni Biofilm in Different Enological Conditions

2019

International audience; Chardonnay wine malolactic fermentations were carried out to evaluate the chemical transfers occurring at the wood/wine interface in the presence of two different bacterial lifestyles. To do this, Oenococcus oeni was inoculated into must and wine in its planktonic and biofilm lifestyles, whether adhering or not to oak chips, leading to three distinct enological conditions: (i) post-alcoholic fermentation inoculation in wine in the absence of oak chips, (ii) post-alcoholic fermentation inoculation in wine in the presence of oak chips, and (iii) co-inoculation of both Saccharomyces cerevisiae and O. oeni directly in Chardonnay musts in the presence of oak chips. Classi…

Metabolism and Transport of Sugars and Organic Acids by Lactic Acid Bacteria from Wine and Must

2017

Oenococcus oeni and other heterofermentative lactic acid bacteria from wine are able to grow at the expense of hexose and pentose sugars using the phosphoketolase pathway. Fermentation of hexoses is limited by low activity of the enzymes for ethanol production. Erythritol is formed as an alternative product, but the enzymes of the pathway are mostly unknown. Presence of fructose, citrate, pyruvate or O2 results in a shift of hexose fermentation to acetate at the expense of ethanol. O. oeni and other lactic acid bacteria are able to degrade organic acids of wine such as citrate, l-malate, pyruvate, l-tartrate and fumarate. The pathways for tartrate and fumarate degradation are known only in …

Microevolutionary response of a gut nematode to intestinal inflammation.

2017

7 pages; International audience; Parasitic helminths interfere with the immune response of their hosts to establish long-lasting, chronic infections. While favorable to the parasite, the capacity to dampen the immune response can also provide a benefit to the host in terms of reduced risk of immune disorders and immunopathology. The immunomodulatory role of nematodes has been exploited in clinical trials to treat a number of inflammatory and immune diseases. However, how parasites adapt to an inflammatory environment remains a poorly explored question. Here, we conducted a serial passage experiment where the gut nematode Heligmosomoides polygyrus was maintained for nine generations in mice …

Effect of video capture time on sperm kinematic parameters in breeding boars

2019

Abstract Computer Assisted Semen Analysis (CASA) technology is being a common tool in the seminal analysis for seminal doses production in farm animals. The aim of the present work was to define the optimal capturing time for a correct evaluation of boar sperm motility. Six sexually mature boars from the Topigs Lines, were used as semen donors. ISASv1 CASA-Mot system was used with an image acquisition rate of 50 Hz for two seconds capturing. Obtained video frames were fragmented into four segments corresponding to 0.5, 1.0, 1.5 and 2.0 s. ISASD4C20 counting chambers, warmed at 37 °C were used. Total and progressive motility were not affected by capture time. Capture time had a significant e…