Sentinel lymph node mapping with computed tomography lymphography for mast cell tumours and a comparison between regional and sentinel lymph node histological status: Sixty-two cases

It is known that the regional lymph node (RLN) may not correspond to the sentinel lymph node (SLN) (the first lymph node draining the tumour), and many diagnostic techniques have recently been aimed at its detection. Although lymphoscintigraphy is the gold standard in both human and veterinary medicine for SLN mapping, it is relatively unavailable in veterinary medicine due to costs and difficult management of the radiotracer. This prospective study evaluated, as a first aim, the feasibility and sensitivity of the computed tomography lymphography (CTL) in detecting the SLN in 62 mast cell tumours (MCTs). The second aim was to evaluate the accuracy of the CTL in identifying the most representative lymph node of the patient's lymphatic status; the histological status of the SNL was compared with that of the RLN, to see in how many cases the patient's stage would have changed according to the RLN. When the RLN turned out to be also the SLN it was decided to excise, as a control LN, the one localised in the neighbourhood of the MCT (neighbouring lymph node; NLN). The detection rate was 90%, with failure of SLN identification in six cases. In 18 (32%) of 56 MCTs with a diagnostic CTL, the SLN did not correspond to the RLN. Forty-five MCTs were surgically removed, together with their corresponding SLN and RLN/NLN. Since the clinical stage of the patient would have changed in only 7% of cases, CTL is a reliable method of detecting the SLN and, for staging purposes, there is no need to remove other LNs.     

Enhancement of alkalinity tolerance in two cucumber genotypes inoculated with an arbuscular mycorrhizal biofertilizer containing Glomus intraradices

The aim of the present study was to determine whether arbuscular mycorrhizal (AM) inoculation with a biofertilizer containing clays as granular carriers, leek root pieces and Glomus intraradices spores could improve alkalinity tolerance of two cucumber genotypes, and to study the changes induced by AM at agronomical and physiological level. A greenhouse experiment was carried out to determine yield, growth, fruit quality, net photosynthesis (A_CO2), electrolyte leakage, and mineral composition of two cucumber (Cucumis sativus L.) genotypes (hybrid “Ekron” or open-pollinated variety “Marketmore”) with inoculated and noninoculated arbuscular mycorrhizal biofertilizer. Plants were supplied with nutrient solutions at two pH values (6.0 or 8.1). The high pH nutrient solution had the same basic composition with an additional 10 mM NaHCO₃ and 0.5 g l⁻¹ CaCO₃. The percentage root colonization was higher in “Marketmore” (21.8%) than “Ekron” (12.7%). Total and marketable yield and total biomass were significantly higher by 189%, 213%, and 77%, respectively, with Ekron in comparison to those recorded with Marketmore. The highest crop performance with Ekron in comparison to Marketmore was due to the improved nutritional status (higher N, P, K, Ca, Mg, Fe, Mn, and B), higher leaf area, and net photosynthesis. Increasing the concentration of NaHCO₃ from 0 to 10 mM in the nutrient solution significantly decreased yield, plant growth, A_CO2, N, P, Fe, Cu, Zn, Mn, and B concentration in leaf tissue, whereas the electrolyte leakage increased. The inoculated plants under alkaline conditions had higher total, marketable yield, and total biomass than noninoculated plant. Mycorrhizal cucumber plants grown under alkaline conditions had a higher macronutrient concentration in leaf tissue compared to noninoculated plants. The highest yield and biomass production in inoculated plants seems to be related to the capacity of maintaining higher net A_CO2 and to a better nutritional status (high P, K, Mg, Fe, Zn, and Mn and low Na accumulation) in response to bicarbonate stress with respect to −AM plants.     

Persistence of azadirachtin residues on olives after field treatment

In this work an HPLC method for the determination of azadirachtin residues on olives was developed, and the field degradation kinetics of the pesticide was studied. In field trials the active ingredient (a.i.) decay had a half-life time of 0.8 days, which was too short to show a good efficacy of treatment. The mechanism of disappearance of the pesticide studied with model systems showed that it was unrelated to evaporation, thermodegradation, and co-distillation, but it was related to photodegradation. The high photodegradation rate of commercial formulations calls for the need to test different formulates in order to increase the persistence of the residue and thus the pesticide's efficacy.     

Host-parasite relationships in tobacco plants infected with a root-knot nematode (<Emphasis Type="Italic">Meloidogyne incognita</Emphasis>) population from the Azores

During a nematode survey, severe infections of tobacco feeder roots and heavy soil infestations byMeloidogyne incognita race 1 were found in S. Miguel (Azores islands, Portugal). This is the first record ofM. incognita infection of tobacco in Azores. Morphology of various life stages, analysis of the esterase electrophoretic pattern and differential host tests were used for nematode characterization and identification. Nematode-induced mature galls were spherical and/or ellipsoidal and usually contained more than one female, males and egg masses with eggs. Feeding sites were characterized by the development of giant cells that contained granular cytoplasm and many hypertrophied nuclei. Giant cell cytoplasm was aggregated along a thickened cell wall. Vascular tissues within galls appeared disorganized. The relationship between the initial nematode population density and growth of tobacco plants was tested in a glasshouse experiment in which inoculum levels varied from 0 to 512 eggs and juveniles (J₂) cm⁻³ of soil. Seinhorst’s model was fitted to height and top fresh weight data of the inoculated and control plants. Tolerance limits with respect to plant height and fresh top weight of tobacco cv. ‘Erzegovina’ plants toM. incognita race 1 were estimated as 1.25 eggs and J₂ cm⁻³ of soil. The maximum nematode reproduction rate was 404.7 at an initial population density of 4 eggs and J₂ cm⁻³ of soil. http://www.phytoparasitica.org posting March 2, 2004.     

Haemothorax associated with Angiostrongylus vasorum infection in a dog

Angiostrongylosis was diagnosed in a dog presenting with haemothorax on the basis of detection of Angiostrongylus vasorum first-stage larvae both in the pleural effusion and in faeces. A one-year-old, male, mixed-breed dog was presented with fever, depression and persistent cough of one month's duration. Clinical examination revealed temperature of 39.5 degrees C, loud bronchovesicular sounds on thoracic auscultation and attenuated cardiac sounds. Thoracic radiographs showed a moderate bilateral pleural effusion and a diffuse interstitial pulmonary pattern, with an alveolar pattern in one lobe. Routine haematology revealed anaemia and leucocytosis with eosinophilia, basophilia and thrombocytopenia. Coagulation assays showed a consumptive coagulopathy resembling disseminated intravascular coagulation. The relationship between haemothorax and the presence of A vasorum larvae in the pleural effusion is discussed. The dog was successfully treated with fenbendazole until negative for larvae on faecal examination. This case report indicates that A vasorum infection should be considered as a possible aetiological cause of haemothorax in dogs.     

Interaction of four monoterpenes contained in essential oils with model membranes: implications for their antibacterial activity

The present article reports the antimicrobial efficacy of four monoterpenes (thymol, carvacrol, p-cymene, and gamma-terpinene) against the Gram-positive bacterium Staphylococcus aureus and the Gram-negative bacterium Escherichia coli. For a better understanding of their mechanism of action, the damage caused by these four monoterpenes on biomembranes was evaluated by monitoring the release, following exposure to the compounds under study, of the water-soluble fluorescent marker carboxyfluorescein (CF) from large unilamellar vesicles (LUVs) with different lipidic composition (phosphatidylcholine, PC, phosphatidylcholine/phosphatidylserine, PC/PS, 9:1; phosphatidylcholine/stearylamine, PC/SA, 9:1). Furthermore, the interaction of these terpenes with dimyristoylphosphatidylcholine multilamellar vesicles as model membranes was monitored by means of differential scanning calorimetry (DSC) technique. Finally, the results were related also with the relative lipophilicity and water solubility of the compounds examined. We observed that thymol is considerably more toxic against S. aureus than the other three terpenes, while carvacrol and p-cymene are the most inhibitory against E. coli. Thymol and carvacrol, but not gamma-terpinene and p-cymene, caused a concentration-dependent CF leakage from all kinds of LUVs employed; in particular, thymol was more effective on PC and PC/SA LUVS than on PC/PS vesicles, while carvacrol challenge evoked a CF leakage from PC/PS LUVs similar to that induced from PC/SA LUVs, and lower than that measured with PC vesicles. Concerning DSC experiments, these four terpenes caused a decrease in Tm and (especially carvacrol and p-cymene) DeltaH values, very likely acting as substitutional impurities. Taken together, our findings lead us to speculate that the antimicrobial effect of thymol, carvacrol, p-cymene, and gamma-terpinene may result, partially at least, from a gross perturbation of the lipidic fraction of the plasmic membrane of the microorganism. In addition to being related to the physicochemical characteristics of the compounds (such as lipophilicity and water solubility), this effect seems to be dependent on the lipidic composition and net surface charge of the microbic membranes. Furthermore, the compounds might cross the cell membranes, thus penetrating into the interior of the cell and interacting with intracellular sites critical for antibacterial activity.     

Mitigation of alkaline stress by arbuscular mycorrhiza in zucchini plants grown under mineral and organic fertilization

A greenhouse experiment was carried out during the spring–summer 2009 to test the hypotheses that: (1) arbuscular‐mycorrhizal (AM) inoculation with a biofertilizer containing Glomus intraradices gives an advantage to overcome alkalinity problems, (2) mineral fertilization is more detrimental to AM development than organic fertilization on an equivalent nutrient basis. Arbuscular mycorrhizal (AM) and non‐AM of zucchini (Cucurbita pepo L.) plants were grown in sand culture with two pH levels in the nutrient solution (6.0 or 8.1) and two fertilization regimes (organic or mineral). The high‐pH nutrient solution had the same basic composition as the low‐pH solution, plus an additional 10 mM NaHCO₃ and 0.5 g L^–1 CaCO₃. Increasing the concentration of NaHCO₃ from 0 to 10 mM in the nutrient solution significantly decreased yield, plant growth, SPAD index, net assimilation of CO₂ (A_CO2), N, P, Ca, Mg, Fe, Mn, and Zn concentration in leaf tissue. The +AM plants under alkaline conditions had higher total, marketable yield and total biomass compared to –AM plants. The higher yield and biomass production in +AM plants seems to be related to the capacity of maintaining higher SPAD index, net A_CO2, and to a better nutritional status (high P, K, Fe, Mn, and Zn and low Na accumulation) in response to bicarbonate stress with respect to –AM plants. The percentage root colonization was significantly higher in organic‐fertilized (35.7%) than in mineral‐fertilized plants (11.7%). Even though the AM root colonization was higher in organic‐fertilized plants, the highest yield and biomass production were observed in mineral‐fertilized plants due to the better nutritional status (higher N, P, Ca, and Mg), higher leaf area, SPAD index, and A_CO2.     

Phytocomplexes from liquorice (Glycyrrhiza glabra L.) leaves--chemical characterization and evaluation of their antioxidant, anti-genotoxic and anti-inflammatory activity

Three extracts of different polarities of Glycyrrhiza glabra L. leaves were characterized and evaluated for their antioxidant, anti-genotoxic and anti-inflammatory activity. In total, thirty components have been identified and quantified through the use of liquid chromatography (LC) with ultraviolet-visible diode-array-detector (UV-vis-DAD) and mass spectrometry (MS). The main components belong to the polyphenols family, being flavonoid and dihydrostilbene derivatives. The extracts have been investigated for their antioxidant, anti-genotoxic and anti-inflammatory activities, which are fundamental requirements of efficacious chemo-preventive agents. The ethyl acetate extract proved to be the most valuable, evidently for the conspicuous presence of several polyphenols, namely flavonoids and dihydrostilbenes.     

Effect of water, soil temperatures, and exposure times on the survival of the sugar beet cyst nematode, heterodera schachtii

ABSTRACT The effect of different combinations of temperatures and exposure times on the mortality of Heterodera schachtii eggs was assessed in two different experiments under laboratory conditions. In the first experiment, cysts in water were exposed to 25, 35, 37.5, 40, 42.5, 45, 47.5, 50, or 52.5 degrees C for a maximum period of 2 h. In the second experiment, cysts in naturally infested soil were exposed to 25, 32.5, 35, 37.5, 40, 42.5, or 45 degrees C for a minimum period of 2 h to a maximum of 2,048 h. Viability of eggs in cysts was assessed by a hatching test in 3 mM zinc chloride solution. Viability in water was suppressed after 2-h exposure at 50 degrees C and inhibited after 1 to 2 h at 52.5 degrees C. Emergence of juveniles from cysts in soil was greater at the lower temperature x exposure time combinations and suppressed at higher combinations. Egg mortality started after exposure for 256 h at 40 degrees C, 32 h at 42.5 degrees C, and 16 h at 45 degrees C, and 81, 31, and 7 h of exposure were necessary to kill 50% of the nematode egg population at 40, 42.5, and 45 degrees C, respectively. The data fitted the models P(t) = P(0)10(-t/ (q + mT)) and P(T1) = P(T0)10(-T/(z - pt)) for m = -0.0111, q = 0.8238, z = 2.444, and p = -0.23.     

Doppler echocardiographic evidence of pulmonary hypertension in dogs: a retrospective clinical investigation

Pulmonary hypertension (PH) decreases resistance to fatigue and life expectancy. The aim of this study was to correlate some indirect Doppler indices of PH with tricuspid and pulmonary regurgitation criteria and to relate PH on different indices with the severity of clinical signs. Furthermore the pathogenetic mechanisms associated to PH development were discussed. Dogs with Doppler echocardiographic evidence of PH diagnosed by assessment of pulmonary and tricuspid regurgitant jet velocity were selected, their clinical records were reviewed and a clinical score was computed. Seventeen cases of PH were identified. The degree of PH was assessed based on systolic or diastolic pulmonary pressure and the indirect Doppler indices (AT/ET and Tei Index) were calculated; data were statistically evaluated. Indirect Doppler indices were calculated also in a control group of seven healthy dogs. The most common clinical signs were coughing, dyspnea and syncope; the most common condition associated to PH development was the left-sided valvular heart disease. A significant positive correlation was found between Tei Index and both the systolic pressure and the severity of PH while no correlations were found between PH on different indices and clinical score and/or severity of clinical signs. Results of this study suggest that Tei-index could be an useful support not only to reveal PH but also to give information on the severity of PH. The clinical picture in dogs with PH is apparently unpredictable and not strictly correlated with the severity of PH.