Fusarium solani hyalohyphomycosisin loggerhead sea turtles (Caretta caretta): a diagnostic and therapeutical challenge.

Fusarium spp. are pathogens plants, animals and humans, isolated from soil, plants and water systems. They are distributed worldwide and include saprotrophic, biotrophic­pathogenic or endophytic fungi, or producers of mycotoxins (fumonisins). Human isolates are becoming the leading mycosis affecting immunocompromised patients and frequently involved in mycoses of aquatic mammals and reptiles, included sea turtles or their eggs. Here reported are three severe cases of unusual localizations of Fusarium in loggerhead sea turtle (Caretta caretta) and their diagnostic, therapeutic and clinical output. In the clinical practice, correct genus­level identification of Fusarium species is critically important to enable correct treatment as in vitroantifungal susceptibility testing is mandatory for each Fusarium­like isolate. For this reason, susceptibility testing can significantly help the practitioner in choosing the most appropriate therapeutic protocol.

Change in vascular smooth muscle response to 5-HT due to short- or long-term endothelial denudation of the bovine digital vein.

Several chronic progressive vascular diseases, such as laminitis, show vasocontractile dysfunction that might evolve into reperfusion injury and/or vessel structural remodelling, which may be traced back to aberrant endothelial function. In the present study, the vasomotor responses of bovine digital veins (BDVs) to 5-hydroxytryptamine (5-HT) were investigated in blood vessels, with and without endothelium present, and in samples deprived of endothelium before or after overnight incubation in tissue culture medium, to evaluate the effects of short- and long-term endothelial damage on vascular smooth muscle (VSM) reactivity. No significant effects were observed in the blood vessels tested immediately after the removal of endothelium. In contrast, a significant increase in VSM reactivity to 5-HT was seen in vessels incubated without endothelium. This long-term change in smooth muscle reactivity was prevented by exposure to the nitric oxide (NO) donor nitroprusside (P < 0.01), suggesting that the long-term lack of inhibitory control exerted by endothelium-derived NO is involved in increased VSM reactivity. The RhoA/ROCK pathway inhibitor fasudil reduced VSM hyper-contractility to ~65% (P < 0.001), the superoxide dismutase-mimetic tempol normalised the vascular response and the non-selective COX-inhibitor indomethacin exerted a moderate inhibitory effect (P < 0.05). Thus, over-activation of the RhoA/ROCK pathway and production of reactive oxygen species could account for VSM hyper-reactivity, triggered by long-term endothelium-deprivation in BDVs, suggesting that these biochemical mechanisms are potential targets for controlling the progressive vasocontractile dysfunction of digital veins in animals affected with laminitis.

In vitro efficacy of ribavirin against canine distemper virus.

Despite vaccination, canine distemper virus (CDV) remains one of the important pathogen of dogs with worldwide distribution. Ribavirin (RIB) inhibits replication of measles virus (MV), a morbillivirus closely related to CDV, both in vitro and in vivo. In this report the antiviral activity of RIB against CDV in cell cultures was assessed. Quantitative real-time RT-PCR was used to measure viral RNA in VERO cells infected by CDV and to evaluate the inhibitory effects of RIB. RIB caused a dose- and time-dependent decrease in accumulation of CDV RNA when added after virus adsorption. RIB was highly effective in preventing CDV replication at low concentrations with 50% virus-inhibitory concentrations ranging from 0.02 to 0.05 mM. Such low values were comparable to values displayed by highly susceptible strains of MV. In addition, CDV was passaged sequentially in VERO cell monolayers in the presence of RIB to trigger viral extinction. The virus was no longer detected after three passages, suggesting that error catastrophe is one of the modes of action of RIB against CDV. These findings suggest RIB as a promising tool for the therapy of CD in dogs.

A rapid and simple method for the separation of pure lymphocytes from horse blood.

A method for the separation of pure and viable lymphocytes and granulocytes from the same blood sample in horses was reported. By centrifuging equine heparinized blood at 100 xg for 10 min at room temperature (r.t.), the resulting supernatant plasma was an almost pure (97.71 +/- 0.30%; n = 15) suspension of highly viable (98.72 +/- 0.28%) lymphocytes. When sodium citrate was used as an anticoagulant, lymphocyte suspensions collected in the same manner showed lower purity (87.89 +/- 1.59%; n = 9) and higher yields (56.56 +/- 3.89%, n = 9 versus 36.11 +/- 2.23%, n = 15). Where needed, a further centrifugation at 250 xg for 3 min (r.t.) of heparinized lymphocyte preparations removed an average of 87.39% (n = 15) contaminating platelets. A suspension of 85.96 +/- 2.20% pure granulocytes (93.23 +/- 1.74% neutrophils; n = 14) with minimal contamination by erythrocytes and high viability (93.11 +/- 1.26%) was obtained by performing a flash red blood cell lysis on the white-greyish layer resulting from the centrifugation of the heparinized blood samples. Among the several methods available, the procedure described herein is easy, rapid, cheap and reproducible.

Depletion and bioavailability of imidocarb residues in sheep and goat tissues.

The residual depletion of a commercial product containing imidocarb dipropionate in sheep and goat tissues was investigated. Additionally, the oral bioavailability of residues was determined in rats to evaluate the extent to which tissue imidocarb residues could be reabsorbed by consumers. Ten ewes and 5 goats were administered im with a commercial formulation containing imidocarb dipropionate (Carbesia cavalli, Shering-Ploug 121.15 mg/ml) at the single dose of 3 mg/kg bw corresponding to 2.1 mg/kg bw imidocarb base. Two sheep and 1 goat were slaughtered 15, 30, 60, 90 or 120 d after dosing and samples of muscle, injection site muscle, liver, omental and subcutaneous fat, and kidneys were collected. Samples of cerebral hemisphere, cerebellum, olfactory bulb, pineal and pituitaryglands were dissected. For the residue bioavailability study 7 groups of3 Wistar rats each, were dosed by gavage with imidocarb dipropionate standard in water (group 2, 3 and 4) or with imidocarb as a liver residue collected from prior dosed animals (group 5, 6 and 7) at 8.4. 16.8 or 33.6 microg/kg of imidocarb base respectively, for 5 d. Group I was control. All animals were sacrificed the day after the last drug administration and livers were collected. The highest drug levels in sheep and goats occurred in liver and kidney, suggesting that these tissues are targets for residues; muscle had negligible importance as storage tissue. Goats had a lower storage capability than sheep. The residue profile in sheep liver and omental fat showed a 30-d storage period to reach maximum concentrations, and suggested that imidocarb is redistributed. The high and long-lasting concentrations in brain showed its capacity to cross the blood-brain barrier and caused concern for potential neurotoxic effects. Detectable concentrations of imidocarb were not found in rat liver.