Expression of verocytotoxic Escherichia coli antigens in tobacco seeds and evaluation of gut immunity after oral administration in mouse model

Verocytotoxic Escherichia (E.) coli strains are responsible for swine oedema disease, which is an enterotoxaemia that causes economic losses in the pig industry. The production of a vaccine for oral administration in transgenic seeds could be an efficient system to stimulate local immunity. This study was conducted to transform tobacco plants for the seed-specific expression of antigenic proteins from a porcine verocytotoxic E. coli strain. Parameters related to an immunological response and possible adverse effects on the oral administration of obtained tobacco seeds were evaluated in a mouse model. Tobacco was transformed via Agrobacteium tumefaciens with chimeric constructs containing structural parts of the major subunit FedA of the F18 adhesive fimbriae and VT2e B-subunit genes under control of a seed specific GLOB promoter. We showed that the foreign Vt2e-B and F18 genes were stably accumulated in storage tissue by the immunostaining method. In addition, Balb-C mice receiving transgenic tobacco seeds via the oral route showed a significant increase in IgA-positive plasma cell presence in tunica propria when compared to the control group with no observed adverse effects. Our findings encourage future studies focusing on swine for evaluation of the protective effects of transformed tobacco seeds against E. coli infection.     

Extraction of cellulose nanowhiskers from natural fibers and agricultural byproducts

In this work the feasibility of extracting cellulose from cotton, sisal and flax fibers, corn stover and rice husk by means of usual chemical procedures such as acid hydrolysis, chlorination, alkaline extraction, and bleaching was analyzed. Cellulose nanowhiskers from these sources, and from commercial cellulose, were produced by the acid hydrolysis of the obtained celluloses. The final products were characterized by means of Thermogravimetric Analysis (TGA), Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electronic Microscopy (SEM) and Atomic Force Microscopy (AFM). The chemical procedure used to obtain cellulose nanowhiskers was effective in all cases but differences on the thermal stability, chemical composition, crystallinity and morphology were found due to the dissimilar nature of the different sources. Thus, this work demonstrates that the morphology and physical properties of cellulose nanowhiskers synthesized by the same conditions are strongly dependent on their source.     

Effect of thinning on above-ground biomass accumulation in a Douglas-fir plantation in southern Italy

We investigated the effects of a long-term thinning experiment on the distribution of above-ground biomass of Douglas-fir(Pseudotsuga menziesii [Mirb.]Franco var. menziesii) in a plantation in southern Italy.Allometric equations were used to estimate biomass and partitioning to stem and crown compartments. Variation in biomass stock estimated with allometric equations were evaluated according to seven thinning treatments: geometric-systematic(1 row every 3), selective(light-moderate-heavy), mixed systematic-selective(1 row every 4, 1 row every 5), unthinned(control). Over the experimental period of 13 years, current annual increments of carbon were lower(3.4 Mg ha~(-1)year~(-1)) in control plots than in treated plots. At age 30, plots subjected to light selective thinning showed higher values of above-ground biomass(249.7 Mg ha~(-1)). The biomass harvested with this treatment was 29.3 Mg ha~(-1), and the mean annual increment of carbon over 13 years was 4.8 Mg ha~(-1). Our results showed that light thinning stimulated increase in carbon stock, with a minimal loss of carbon during the treatment and a current annual increment of carbon higher than in control sub-plots and sub-plots thinned using systematic methods. This treatment yielded least carbon emissions and we affirm it has discrete global warming mitigation potential.     

Age-Dependent Bioaccumulation of Organochlorine Compounds in Fish and their Selective Biotransformation in Top Predators from Lake Maggiore (Italy)

Fish and piscivorous bird eggs collected in 2003 from Lake Maggiore (Italy), were analysed for PCB and DDT contamination. Lake Maggiore has been severely polluted by DDT through production of the pesticide within its catchment. Although agricultural application of DDT was banned in Italy in the 1978, industrial production continued until 1996, with enough contamination of water and soil for serious bioaccumulation in the lake biota. PCB and DDT concentrations in a whitefish (Coregonus macrophthalmus Nusslin 1882) were seen to be dependent on season and fish age, but not on sex. The average increase of the lipid-normalised concentration of DDTs and PCBs was two-fold across season and also across age, resulting in an overall increase of four fold. The seasonal variation was related to the eco-physiological cycle of the fish and to the contamination dynamic of the lake, while the effect of the fish age was explained on the base of biomagnification-related mechanisms. A fugacity model was applied to predict the age-dependent bioaccumulation potential of PCBs, whose concentrations were rather stable in recent years in the lake. Predicted values for compounds with negligible biotransformation were in good agreement with experimental data (calculated vs. experimental mean difference of 14%), and a relationship between the increase of experimental age-dependent concentration and K _ow was observed. The good correspondence between the predicted and the measured values for most PCB congeners confirmed the general inability of fishes to biotransform these compounds. On the contrary, the importance of biotransformation processes was recognised in birds; eggs of a fish eating bird (Podiceps cristatus) from the same area selectively bioaccumulated p,p′-DDE. For PCBs, congener 149 appears to be completely metabolized by the bird species, and congeners 95, 101, 132, 151 and 174 were reduced as well. The role of the meta–para free position on at least one phenyl ring of PCB congeners in biotransformation processes was confirmed.     

COMPUTED TOMOGRAPHIC FEATURES OF INCISOR PSEUDO‐ODONTOMAS IN PRAIRIE DOGS (CYNOMYS LUDOVICIANUS)

Maxillary incisor pseudo‐odontomas are common in pet prairie dogs and can cause progressive respiratory obstruction, while mandibular pseudo‐odontomas are rarely clinically significant. The aim of this retrospective cross‐sectional study was to describe CT features of maxillary and mandibular incisor pseudo‐odontomas vs. normal incisors in a group of pet prairie dogs. All pet prairie dogs with head CT scans acquired during the period of 2013–2015 were included. A veterinary radiologist who was aware of final diagnosis reviewed CT scans and recorded qualitative features of affected and normal incisors. Mean density values for the pulp cavity and palatal and buccal dentin were also recorded. A total of 16 prairie dogs were sampled (12 normal maxillary incisors, 20 confirmed maxillary incisor pseudo‐odontomas, 20 normal mandibular incisors, 12 presumed mandibular incisor pseudo‐odontomas). Maxillary incisors with confirmed pseudo‐odontomas had a significantly hyperattenuating pulp and dentin in the reserve crown and apical zone, when compared to normal maxillary incisors. Pseudo‐odontomas appeared as enlargements of the apical zone with a globular/multilobular hyperattenuating mass formation haphazardly arranged, encroaching on midline and growing caudally and ventrally. Presumed mandibular incisor pseudo‐odontomas had similar CT characteristics. In 60% of prairie dogs with maxillary incisor pseudo‐odontomas, the hard palate was deformed and the mass bulged into the oral cavity causing loss of the palatine bone. The common nasal meatus was partially or totally obliterated in 81.8% of prairie dogs with maxillary pseudo‐odontomas. Findings supported the use of CT for characterizing extent of involvement and surgical planning in prairie dogs with pseudo‐odontomas.     

Antioxidant compounds and antioxidant activity in "early potatoes"

The antioxidant content and the antioxidant capacity of both hydrophilic and lipophilic antioxidant extracts from four "early potato" cultivars, grown in two different locations (Racale and Monteroni), were examined. There was a considerable variation in carotenoid content and weak differences in the ascorbic acid concentration of the examined cultivars of "early potato" and between the harvested locations. An increase in both methanol/water (8:2 v/v) and phosphate buffer soluble (PBS) free phenols (70%) and bound phenols (28%) in the extracts from the cultivars grown at Racale site was found and discussed. Examination of individual phenols revealed that chlorogenic acid and catechin were the major phenols present in potato tuber extracts; a moderate amount of caffeic acid and ferulic acid was also detected. The total equivalent antioxidant capacity (TEAC) was higher in the Racale extracts and a highly positive linear relationship ( R (2) = 0.8193) between TEAC values and total phenolic content was observed. The oxyradical scavenging capacity (TOSC) of methanol/water and PBS extracts of peel and whole potatoes against the reactive oxygen species (ROS) peroxyl radicals, peroxynitrite, and hydroxyl radicals was also analyzed. A highly significant linear correlation ( R (2) = 0.9613) between total antioxidant capacity (as a sum of peroxyl radicals + peroxynitrite) and total phenol content of methanol/water extracts was established. Moreover, proliferation of human mammalian cancer (MCF-7) cells was significantly inhibited in a dose-dependent manner after exposure to potato extracts. These data can be useful for "early potato" tuber characterization and suggest that the "early potato" has a potential as a dietary source of antioxidants.     

ULTRASONOGRAPHIC FEATURES OF GRASS AWN MIGRATION IN THE DOG

The aim of this study was to describe the ultrasonographic features of grass awns in soft tissue. A 10 MHz linear transducer was used. Ultrasound images from 25 dogs (27 awns) were collected and compared with the results from water bath studies using wild oat seeds (Avena spp.) collected in the field. Wild oat seeds were the most common grass awn found in soft tissue of dogs. Ultrasonographically grass awns appeared as a double/triple spindle-shaped echogenic interface within soft tissue. The same appearance was observed in water bath studies. In four dogs, the grass awn was removed surgically with a clamp introduced into a fistulous tract, using sonographic guidance. The grass awn was not found surgically in only three dogs, suggesting more attention during surgery. Ultrasonography is a useful diagnostic imaging technique to identify grass awns within soft tissue.