Host-suitability of black medick (<Emphasis Type="Italic">Medicago lupulina</Emphasis> L.) and additional molecular markers for identification of the pea cyst nematode <Emphasis Type="Italic">Heterodera goettingiana</Emphasis>

A survey was conducted in 16 fields cultivated with broad bean (Vicia faba L.) and garden pea (Pisum sativum L.) in nine localities of Apulia, southern Italy, to determine whether annual weeds were susceptible to the pea cyst nematode (PEACN), Heterodera goettingiana, and could therefore serve as alternate host for the nematode. The results of this study showed that black medick (Medicago lupulina L.) is a good host for the nematode increasing its population levels in the soil in the absence of the primary hosts. The identity of the PEACN was confirmed by integrative taxonomic approaches (classical, and molecular), resulting identical in all cases (broad bean and garden pea, as well as the spontaneous black medick infections). The phylogenetic analyses using ITS and coxI gene regions strongly support the identification of the populations of H. goettingiana from Italy. Also, ITS and coxI gene sequences were obtained from the same cyst, confirming the species identity in comparison to other nematodes and populations in the Goettingiana group, demonstrating that ITS and coxI gene regions of the PEACN are suitable molecular markers for accurate and unequivocal identification of the PEACN. Reproduction and histopathological analyses demonstrated a good host-suitability of black medick to the PEACN. This record enlarges the relatively narrow host-range of the pea cyst nematode and indicates the need to control M. lupulina to avoid the increase of the nematode population in the absence of the main host crop.     

Beef quadriceps hot boning and modified-atmosphere packaging influence properties of injection-enhanced beef round muscles

Two experiments were conducted to examine the effects of hot boning, modified atmosphere packaging, and injection enhancement on the oxidative and sensory properties of beef round muscles. The beef knuckle (quadriceps muscles) was partially hot boned within 1.5 h postmortem from one randomly selected side of each beef carcass (n = 14), whereas the quadriceps on the opposite side remained intact throughout a 48-h chilling period. At 5 d postmortem, biceps femoris, semimembranosus, vastus lateralis, and rectus femoris muscles from both hot- and cold-boned sides were injected with an enhancement solution consisting of water, salt, phosphate, and natural flavorings (rosemary) at either 6 (Exp. 1) or 10% (Exp. 2) of fresh muscle weight. Enhanced muscles were then processed into 2.54-cm-thick steaks, which were allotted randomly to high-oxygen (HiOx; 80% O2:20% CO2) or ultra-low oxygen (LoOx; 80% N2:20% CO2) modified atmosphere packaging. Regardless of hot boning or enhancement, steaks packaged in LoOx had lower thiobarbituric acid-reactive substances values (P < 0.05), more beef flavor intensity (P < 0.05), fewer off flavors (P < 0.05), and were more tender (P < 0.05) than steaks packaged in HiOx. Hot boning the knuckle had no effect on oxidative (P > or = 0.99) and sensory properties (P > or = 0.85). Increasing the level of injection enhancement from 6 to 10% introduced more rosemary and phosphate into the muscles, thereby decreasing the extent of oxidation, but also imparting a nontypical beef flavor. Packaging in LoOx atmosphere offered the optimal result of decreased oxidation and improved tenderness, without detriment to flavor. Injection enhancement (both 6 and 10%) created off-flavors attributable to the enhancement solution; however, the 10% injection seemed to offer more resistance to lipid oxidation.     

Phenotypic characterization of cryptic Diplodia species by MALDI‐TOF MS and the bias of mycelium age

Detection and identification of fungal cryptic species has been facilitated by DNA sequencing. However, the examination of some phenotypic traits is fundamental for the confirmation of genetic results. MALDI‐TOF mass spectrometry has shown remarkable reliability in the recognition of species‐specific phenotypic markers and has already been tested in several species of fungi. However, even though there is no direct evidence, the age of the mycelium appears to influence the composition of the metabolites detected. In this study, we demonstrate that MALDI‐TOF is a reliable technique to identify suitable metabolites to distinguish three monophyletic species of Diplodia (D. pinea, D. seriata and D. scrobiculata), thus supporting recent DNA results. Nevertheless, different collections of samples over a period of 3 months after inoculation also revealed that the MALDI‐TOF spectra are highly dependent on mycelial age. More importantly, the species‐specific markers emerge only after 1 month of mycelial growth. The methodological and biological implications of these findings are discussed.     

Simultaneous detection of the feline lungworms Troglostrongylus brevior and Aelurostrongylus abstrusus by a newly developed duplex-PCR

In addition to Aelurostrongylus abstrusus (Strongylida: Angiostrongylidae), referred to as the feline lungworm, Troglostrongylus brevior (Strongylida: Crenosomatidae) has recently been identified as an agent of bronco-pulmonary infestations in cats. These two parasites have a similar biology, share ecological niches, potentially co-infesting cats, but are difficult to be differentiated due to the morphological similarities of their first-stage larvae (L1). This paper describes a molecular tool, based on single-step duplex polymerase chain reaction (duplex-PCR) on the ribosomal internal transcribed spacer 2 region (ITS-2) for the simultaneous detection and differentiation of T. brevior and A. abstrusus. L1 of both species were collected from faecal samples, morphologically identified, and single larval specimens isolated. An aliquot of faeces was used as a test sample for a case of mixed natural infestation. The duplex-PCR was performed using species-specific forward primer sets for the ITS-2 region (i.e., A. abstrusus: 220 bp; T. brevior: 370 bp). The detection limit of the molecular assay was also assessed by serial dilutions of DNA from single larvae of both species (from ～4.0 to 4.0 × 10^?5 μg/μl). The duplex-PCR carried out on individual DNA samples was able to detect as low as 5.2 × 10^?3 μg/μl of DNA for A. abstrusus, 4.9 × 10^?3 μg/μl for T. brevior, and as low as 4.0 × 10^?3 μg/μl for samples containing both species. Species-specific bands of the expected sizes and two bands were simultaneously amplified from the faecal sample containing both species. The phylogenetic analyses of the ITS-2 sequences here examined and those available for other metastrongyloids were concordant in clustering them with those of other Troglostrongylus brevior and A. abstrusus sequences available in GenBank database. This molecular approach proved to be effective and highly sensitive for the simultaneous detection of the two lungworms species and it might be used for molecular epidemiological studies and for monitoring therapeutic protocols.     

EGFR overexpression in canine primary lung cancer: pathogenetic implications and impact on survival

This study reports the main clinicopathological features of primary lung cancer (PLC) in 37 dogs, with special regard to the pathogenetic and prognostic role of epidermal growth factor receptor (EGFR) overexpression. For each case the following characteristics were evaluated: tumour‐node‐metastasis (TNM) stage, tumour histotype, histological grade, mitotic activity and immunohistochemical expression of EGFR. In samples with available normal lung tissue, the amount of background anthracosis was also measured by image analysis. In 27 tumours (73%) a variable number of cells (20–100%) stained positively for EGFR. The proportion of EGFR‐positive tumours was significantly higher in cases with background anthracosis, and the amount of anthracosis was correlated with the percentage of positive tumour cells. Additionally, a trend towards shortened survival for the high EGFR group was observed. These findings suggest an involvement of EGFR signalling pathway in canine PLC, a negative prognostic significance of protein overexpression and its potential implication in air pollution carcinogenesis.     

Acclimation to partial shading or full sunlight determines the performance of container-grown Fraxinus ornus to subsequent drought stress

Cultivation techniques in the nursery aimed to improve tolerance to abiotic stresses after planting in the landscape may have great ecological value. Here we tested the hypothesis that the irradiance at which plants grow in the nursery may impact on their responses to a subsequent drought stress. Measurements of relevant morpho-anatomical, physiological and biochemical traits were conducted in Fraxinus ornus, a member of the Oleaceae family of increasing interest as an urban tree. Leaves developed under moderate shade displayed a lower ability to preserve water balance, thus suffering from a greater decline in net CO₂ assimilation than leaves acclimated to full sunlight, when subsequently exposed to drought stress. Shaded leaves also displayed an inherently lower capacity to dissipate excess radiant energy through nonphotochemical quenching, thus suffering from greater oxidative damage than sun leaves under drought. These results indicate that sunlight irradiance at which container-grown ash trees grow in the nursery may tightly affect the tolerance to subsequent drought stress. This may have great value for enhancing the establishment of container-grown plants in the landscape, as fully leaved plants may suffer from severe drought stress during early stages of acclimation in the landscape.     

Retinal dystrophy: development retarded by galactose feeding in spontaneously hypertensive rats

Retinal photoreceptor cell dystrophies have been widely observed in humans and in animals, but pathogenetic mechanisms are known in only a few such disorders, and successful therapeutic intervention has been reported in fewer still. Spontaneously hypertensive albino rats develop a retinal photoreceptor cell dystrophy with onset late in the first year or early in the second year of life. Between 60 and 70 percent of the animals are affected. A substantial reduction in the prevalence and severity of the dystrophy occurred in such animals whose diet contained 30 percent (by weight) D-galactose. Neither an inhibitor of the enzyme aldose reductase, present in the diet, nor diabetes mellitus, induced by streptozotocin, had any statistically significant influence on the dystrophy. Ambient light and systolic blood pressure levels also did not seem to influence the course of the disorder. The mechanism by which galactose exerts its effect is unknown, but a mutant enzyme with an elevated Michaelis constant (Km) for galactose is plausible.