Assessment of anti-bovine IL4 and IFN gamma antibodies to label IL4 and IFN gamma in lymphocytes of the koala and brushtail possum     

Higgins DP  Hemsley S  Canfield PJ 《Veterinary immunology and immunopathology》2004,101(3-4):153-160

We assess anti-bovine IL4 and IFN gamma (IFNg) antibodies for their ability to label IL4 and IFNg in koala (Phascolarctos cinereus), common brushtail possum (Trichosurus vulpecula) and mountain brushtail possum (Trichosurus caninus) lymphocytes using flow cytometry and immunohistochemistry to determine their applicability to studies of host response to intracellular pathogens. Anti-IFNg labelled a product of PMA-ionomycin stimulated sheep, koala and possum lymphocytes. High intensity labelling was not reduced by blocking non-specific binding with 10% FCS; and non-permeabilised koala lymphocytes labelled less, demonstrating that the labelled product was intracellular. The anti-IL4 antibody labelled variably more cells than the irrelevant antibody in some stimulated and non-stimulated preparations in all species but intensity of this labelling was similar to that of cells labelled with the irrelevant antibody. In this study, the antibodies did not label frozen or formalin-fixed tissues in a range of immunohistochemical techniques. We expect the anti-IFNg antibody to be effective in evaluating Th1 responses of koalas and possums exposed to various host, pathogen and environmental factors and add to the limited tools available for investigating the pathogenesis of marsupial diseases, especially those caused by intracellular organisms, such as tuberculosis of brushtail possums and chlamydial disease of koalas.  相似文献   

Gorillas are a host for Dientamoeba fragilis: an update on the life cycle and host distribution     

Stark D  Phillips O  Peckett D  Munro U  Marriott D  Harkness J  Ellis J 《Veterinary parasitology》2008,151(1):21-26

Dientamoeba fragilis is a gastrointestinal protozoan that has a worldwide distribution and is emergeing as a common cause of diarrhea. As D. fragilis has a propensity to cause chronic illness with symptoms similar to irritable bowel syndrome (IBS) it is not surprising that some patients with D. fragilis are misdiagnosed as having IBS. In contrast to most other pathogenic protozoa very little is known about its life cycle, epidemiology and mode of transmission. What role animal reservoirs play in the transmission of this parasite is unknown. Consequently we undertook a prospective study to determine the host distribution of D. fragilis. Over a 2-year-period, 608 faecal samples from a wide range of animal and bird species, including pigs and other food species, were screened using permanent stained smears for the presence of D. fragilis. Trophozoites of D. fragilis were only detected in Western lowland gorillas (3/10) (Gorilla g. gorilla) and confirmed by PCR targeting the SSU rRNA gene. The limited host range detected suggests human infection may not involve transmission from other animal species. In addition, we provide an update on the limited knowledge about the life cycle of this parasite and its host distribution.  相似文献   

Beta-N-methylamino-l-alanine: LC-MS/MS Optimization,Screening of Cyanobacterial Strains and Occurrence in Shellfish from Thau,a French Mediterranean Lagoon     

Damien Réveillon  Eric Abadie  Véronique Séchet  Luc Brient  Véronique Savar  Michèle Bardouil  Philipp Hess  Zouher Amzil 《Marine drugs》2014,12(11):5441-5467

β-N-methylamino-l-alanine (BMAA) is a neurotoxic non-protein amino acid suggested to be involved in neurodegenerative diseases. It was reported to be produced by cyanobacteria, but also found in edible aquatic organisms, thus raising concern of a widespread human exposure. However, the chemical analysis of BMAA and its isomers are controversial, mainly due to the lack of selectivity of the analytical methods. Using factorial design, we have optimized the chromatographic separation of underivatized analogues by a hydrophilic interaction chromatography coupled to tandem mass spectrometry (HILIC-MS/MS) method. A combination of an effective solid phase extraction (SPE) clean-up, appropriate chromatographic resolution and the use of specific mass spectral transitions allowed for the development of a highly selective and sensitive analytical procedure to identify and quantify BMAA and its isomers (in both free and total form) in cyanobacteria and mollusk matrices (LOQ of 0.225 and 0.15 µg/g dry weight, respectively). Ten species of cyanobacteria (six are reported to be BMAA producers) were screened with this method, and neither free nor bound BMAA could be found, while both free and bound DAB were present in almost all samples. Mussels and oysters collected in 2009 in the Thau Lagoon, France, were also screened, and bound BMAA and its two isomers, DAB and AEG, were observed in all samples (from 0.6 to 14.4 µg/g DW), while only several samples contained quantifiable free BMAA.  相似文献   

Polar interactions in flavan-3-ol adsorption on solid surfaces     

Cartalade D  Vernhet A 《Journal of agricultural and food chemistry》2006,54(8):3086-3094

The adsorption of flavan-3-ol monomers and grape seed procyanidin fractions of different mean degrees of polymerization was studied on three surfaces by means of adsorption isotherms. Reversibility upon dilution was also investigated. These surfaces were three polymeric microfiltration membranes, presenting close Lifshitz-van der Waals components of their surface tension but differing in their surface polar properties. The electron-donor character of the surface was of primary importance for the adsorption of nongalloylated monomers. Increasing the number of phenolic rings above two (galloylated monomers and procyanidins) sharply enhanced flavan-3-ol affinity for surfaces whatever their polarity. However, maximum adsorbed amounts were always much higher on the most polar material. The general trend was a partial reversibility with monomers, whereas an irreversible process was evidenced from the lowest molecular weight tannin fractions. This indicated the formation of multiple bonds with surfaces, in accordance with the high affinity type isotherms. The whole results indicated very different mechanisms in the buildup of the adsorbed layers when the surface electron-donor character varied.  相似文献   

Wnt gradient formation requires retromer function in Wnt-producing cells     

Coudreuse DY  Roël G  Betist MC  Destrée O  Korswagen HC 《Science (New York, N.Y.)》2006,312(5775):921-924

Wnt proteins function as morphogens that can form long-range concentration gradients to pattern developing tissues. Here, we show that the retromer, a multiprotein complex involved in intracellular protein trafficking, is required for long-range signaling of the Caenorhabditis elegans Wnt ortholog EGL-20. The retromer functions in EGL-20-producing cells to allow the formation of an EGL-20 gradient along the anteroposterior axis. This function is evolutionarily conserved, because Wnt target gene expression is also impaired in the absence of the retromer complex in vertebrates. These results demonstrate that the ability of Wnt to regulate long-range patterning events is dependent on a critical and conserved function of the retromer complex within Wnt-producing cells.  相似文献