Abnormal Sysmex XT‐2000iV DIFF scattergram in a cat with a prominent mastocytemia

A 2‐year‐old neutered male domestic shorthair cat was presented to the emergency service of the National Veterinary School of Toulouse (France) for acute vomiting and diarrhea with lethargy, inappetence, and adypsia for the past 48 hours. Complete blood counts were performed with the ProCyte DX at the emergency department and with the Sysmex XT‐2000iV at the laboratory 2 weeks later. The scattergrams from the two analyzers revealed similar unusual and abnormal dot plots. The Sysmex XT‐2000iV DIFF scattergram also showed no clear separation between different leukocyte populations. The eosinophil cluster was in an abnormal location compared with that of the “typical” location in a normal cat. A blood smear evaluation revealed the presence of numerous mast cells. Thus, we hypothesized that the Sysmex XT‐2000iV had detected the mast cell population, and this led to errors in the differential counts. To explore this hypothesis, we manually gated on the DIFF scattergram and performed a manual differential on the blood smear. With this new gating strategy, the Sysmex XT‐2000iV and manual differentials were similar. Thus, in the case of systemic mastocytosis, mast cells can be located between the lymphocyte, monocyte, and eosinophil clusters on scattergrams.     

Immunohistochemical characterization of a hepatic neuroendocrine carcinoma in a cat.

A hepatic mass was identified in a 5-year-old, female mixed-breed cat that died spontaneously after a clinical history of progressive emaciation, ptyalism, and persistent coryza. At necropsy, a 7-cm-diameter, yellow-brown, firm, multilobulated tumor was identified in the liver. Microscopically, the mass consisted of neoplastic cells arranged in small, closely packed nests within a thin fibrovascular stroma. These cells were of medium sized and polygonal, with fine argyrophilic cytoplasmic granules. Nuclei were predominantly round with finely stippled chromatin and indistinct nucleoli. Mitotic figures were numerous. Immunohistochemically, most of the neoplastic cells were immunoreactive for chromogranin A, neuron-specific enolase (NSE), and cytokeratin AE1/AE3 and weakly labeled for synaptophysin. The tumor was negative for glial fibrillary acidic protein (GFAP), vimentin, and cytokeratins 5, 6, 8, and 17. Vascular emboli and intrahepatic micrometastasis were also identified with chromogranin A. All these features were consistent with a hepatic neuroendocrine carcinoma and emphasized the importance of using a panel of antibodies to diagnose such rare tumors.     

Evaluation of targeted drenching using Famacha method in Creole goat: reduction of anthelmintic use, and effects on kid production and pasture contamination

Haemonchus infection was monitored for 2 years (six kidding periods) in a Creole goat flock grazing under oceanic-tropical climate. Two hundred and thirty individual does were involved from late pregnancy to weaning. Anaemia diagnoses using Famacha method and packed cell volume (PCV) were compared. The best agreement (Kappa=0.33) was found if anaemia was declared when PCV values fell to 16 or below and Famacha score was 4 or 5. Drenching policy according to Famacha method was compared to systematic drenching policy. Using the Famacha method allowed a dramatic decrease in anthelmintic use during the periparturient period (0.57 individual dose instead of three doses for the control). The proportion of the nematode population on the pasture not derived from previously-treated goats (in refugia) was estimated to about 79% (65-90%) of the pasture contamination derived from the Famacha group. On the average, goats which needed to be drenched produced less than the control or undrenched goats (kid average daily gain was decreased by about 15%). The repeatability of the need for drenching individual does was estimated to 0.41. The older goats or the goats in poorer body condition at kidding needed more drenching than the younger animals and the animals in good body condition. Consequently the Famacha method may be used as an additional tool for the culling management.     

Geosmin causes off‐flavour in arctic charr in recirculating aquaculture systems

The ‘earthy’ and ‘muddy’ off‐flavours in pond‐reared fish are due to the presence of geosmin or 2‐methylisoborneol in the flesh of the fish. Similar off‐flavours have been reported in fish raised in recirculating aquaculture systems (RAS); however, little information is available regarding the cause of these off‐flavours. Our hypothesis was that earthy and muddy off‐flavour compounds, found previously in pond‐raised fish, are also responsible for off‐flavours in fish raised in RAS. In this preliminary study, we examined water, biofilms in RAS and fillets from cultured arctic charr known to have off‐flavours and requiring depuration using instrumental [solid‐phase microextraction procedure and gas chromatograph‐mass spectrometry (GC‐MS)] and human sensory analyses. Geosmin was present in the samples taken from the biofilter and on the side walls of the tanks. Two‐methylisoborneol was only found in low levels in the samples. The GC‐MS results indicated the presence of geosmin in the fillets (705 ng kg^?1), but lower levels were found in the water (30.5 ng L^?1). Sensory analyses also detected an earthy flavour (i.e., geosmin presence) in the fillets, and, therefore, it appears that geosmin is the main compound responsible for the off‐flavour in RAS. Further studies are being performed to identify the microorganisms responsible for geosmin production in RAS.     

Effect of native and allochthonous arbuscular mycorrhizal fungi on Casuarina equisetifolia growth and its root bacterial community

Exotic trees are often planted to recover degraded lands. Inoculation with mycorrhizal fungi can improve their survival. Plant growth is partly dependent on the strain used, but little attention has been paid to the selection of mycorrhizal fungi. The aim of this study was to determine whether the growth of Casuarina equisetifolia L. (Johnson) is affected by two different mycorrhizal inocula generated using fungal spores retrieved from an Australian site (allochthonous soil) and a Senegalese site (native soil) under C. equisetifolia trees. Comparative experiments were conducted with plants in a Senegalese soil, previously sterilized or not, and grown in a greenhouse. At harvest, parameters related to plant growth and mycorrhization were evaluated and soil bacterial communities were compared. Tree growth was significantly influenced by both types of inoculants. In unsterilized soil, plants inoculated with the native inoculant were taller than plants inoculated with the allochthonous inoculant and control plants. The frequency of mycorrhization with both inoculants was higher in unsterilized soil. The strongest effects of the mycorhizosphere on the soil microbiome were obtained with the allochthonous inoculum, and analysis of the taxonomic composition revealed mycorrhizal communities specific to each inoculum. These results suggest that the development of C. equisetifolia and its root bacterial community are dependent on the composition of the mycorrhizal inoculum. The functional consequences of this rhizosphere effect in terms of soil fertility should be further studied to better guide reforestation operations.     

Identification of a Pro-Angiogenic Potential and Cellular Uptake Mechanism of a LMW Highly Sulfated Fraction of Fucoidan from Ascophyllum nodosum

Herein we investigate the structure/function relationships of fucoidans from Ascophyllum nodosum to analyze their pro-angiogenic effect and cellular uptake in native and glycosaminoglycan-free (GAG-free) human endothelial cells (HUVECs). Fucoidans are marine sulfated polysaccharides, which act as glycosaminoglycans mimetics. We hypothesized that the size and sulfation rate of fucoidans influence their ability to induce pro-angiogenic processes independently of GAGs. We collected two fractions of fucoidans, Low and Medium Molecular Weight Fucoidan (LMWF and MMWF, respectively) by size exclusion chromatography and characterized their composition (sulfate, fucose and uronic acid) by colorimetric measurement and Raman and FT-IR spectroscopy. The high affinities of fractionated fucoidans to heparin binding proteins were confirmed by Surface Plasmon Resonance. We evidenced that LMWF has a higher pro-angiogenic (2D-angiogenesis on Matrigel) and pro-migratory (Boyden chamber) potential on HUVECs, compared to MMWF. Interestingly, in a GAG-free HUVECs model, LMWF kept a pro-angiogenic potential. Finally, to evaluate the association of LMWF-induced biological effects and its cellular uptake, we analyzed by confocal microscopy the GAGs involvement in the internalization of a fluorescent LMWF. The fluorescent LMWF was mainly internalized through HUVEC clathrin-dependent endocytosis in which GAGs were partially involved. In conclusion, a better characterization of the relationships between the fucoidan structure and its pro-angiogenic potential in GAG-free endothelial cells was required to identify an adapted fucoidan to enhance vascular repair in ischemia.     

Heparanase and Syndecan-4 Are Involved in Low Molecular Weight Fucoidan-Induced Angiogenesis

Induction of angiogenesis is a potential treatment for chronic ischemia. Low molecular weight fucoidan (LMWF), the sulfated polysaccharide from brown seaweeds, has been shown to promote revascularization in a rat limb ischemia, increasing angiogenesis in vivo. We investigated the potential role of two heparan sulfate (HS) metabolism enzymes, exostosin-2 (EXT2) and heparanase (HPSE), and of two HS-membrane proteoglycans, syndecan-1 and -4 (SDC-1 and SDC-4), in LMWF induced angiogenesis. Our results showed that LMWF increases human vascular endothelial cell (HUVEC) migration and angiogenesis in vitro. We report that the expression and activity of the HS-degrading HPSE was increased after LMWF treatment. The phenotypic tests of LMWF-treated and EXT2- or HPSE-siRNA-transfected cells indicated that EXT2 or HPSE expression significantly affect the proangiogenic potential of LMWF. In addition, LMWF increased SDC-1, but decreased SDC-4 expressions. The effect of LMWF depends on SDC-4 expression. Silencing EXT2 or HPSE leads to an increased expression of SDC-4, providing the evidence that EXT2 and HPSE regulate the SDC-4 expression. Altogether, these data indicate that EXT2, HPSE, and SDC-4 are involved in the proangiogenic effects of LMWF, suggesting that the HS metabolism changes linked to LMWF-induced angiogenesis offer the opportunity for new therapeutic strategies of ischemic diseases.