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591.
Cabrera-Chávez F Iametti S Miriani M de la Barca AM Mamone G Bonomi F 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(1):24-30
Maize is used as an alternative to wheat to elaborate foodstuffs for celiac patients in a gluten-free diet. However, some
maize prolamins (zeins) contain amino acid sequences that resemble the wheat gluten immunodominant peptides and their integrity
after gastrointestinal proteolysis is unknown. In this study, the celiac IgA-immunoreactivity to zeins from raw or nixtamalized
grains, before and after peptic/tryptic digestion was evaluated and their possible immunogenicity was investigated by in silico methods. IgA from some celiac patients with HLA-DQ2 or DQ8 haplotypes recognized two alpha-zeins even after peptic/tryptic
proteolysis. However, digestion affected zeins after denaturation, reduction, and alkylation, used for identification of prolamins
as alpha-zein A20 and A30 by MS/MS sequencing. An in silico analysis indicated that other zeins contain similar sequences, or sequences that may bind even better to the HLA-DQ2/DQ8
molecules compared to the already identified ones. Results concur to indicate that relative abundance of these zeins, along
with factors affecting their resistance to proteolysis, may be of paramount clinical relevance, and the use of maize in the
formulation and preparation of gluten-free foods must be reevaluated in some cases of celiac disease. 相似文献
592.
Giada d'Errico Elena Fanelli Alberto Troccoli Francesco Binazzi Silvia Landi Pio Roversi Francesca De Luca 《Forest Pathology》2020,50(4)
In February 2015, an unexpected windstorm downed five hectares of a European black pine Pinus nigra subsp. laricio forest formation located close to Vallombrosa, Florence (Central Italy). In the following spring, an extensive survey was conducted in the area. Felled trees, stumps and all the suitable plant material were screened for the presence of the pinewood nematode (PWN), Bursaphelenchus xylophilus, by sampling wood and bark. Bark beetles were then collected from the gallery systems on the inner side of bark samples and observed in the laboratory. The following bark beetles were morphologically identified: Ips sexdentatus, Orthotomicus erosus, O. laricis and Pityogenes bidentatusa. The dissection of Ips sexdentatus allowed the extraction of numerous nematodes that were morphologically and molecularly identified as Ektaphelenchoides pini. Conversely, only few nematode specimens were isolated from either pine bark or wood. These individuals could be only molecularly identified and belonged to an undescribed nematode taxon. Even though no PWN was recorded in the investigated sites, our survey allowed the detection of a new association between E. pini and I. sexdentatus on P. nigra. 相似文献
593.
- 1. Amphibians are declining worldwide in response to local and global pressures. Pond‐breeding species are particularly vulnerable to environmental change because they rely on two components of the landscape: aquatic and terrestrial habitats. Agricultural practices are changing rapidly at world and local scales. As a consequence, farm ponds and their surrounding terrestrial landscapes will probably be affected.
- 2. This study investigated the main habitat determinants for the occurrence of four species of newts (genus Triturus) inhabiting the Pays de Herve, a rural area in Belgium. Newt occurrence was determined for 258 ponds and the effect of habitat on distribution determinants was evaluated using generalized linear models.
- 3. Newts were found in 42% of the ponds. Contrary to expectations, the distribution of newts was not positively associated with a high density of ponds. However, a low occurrence of newts and the low water depth of many ponds suggest a low quality of habitats. Proximity to forest, deep water, and an absence of fish in ponds are factors that significantly favour newts, but terrestrial habitat requirements vary among species.
- 4. These results indicate the necessity of maintaining both forest and meadow patches in close proximity to ponds inhabited by newts, and of controlling fish introduction in those ponds. These findings stress the importance of conservation and management of terrestrial and aquatic habitats for maintaining amphibian diversity.
594.
Giovanni Battista Palmegiano Francesco Gai Franco Daprà Laura Gasco Mario Pazzaglia & Pier Giorgio Peiretti 《Aquaculture Research》2008,39(6):587-595
The aim of this research was to evaluate the efficiency of diets with Spirulina and plant oils (POs) inclusion for white sturgeon weaning and their effects on the fatty acid (FA) composition of fish flesh. Three isoproteic (45%) and isoenergetic (21 MJ kg?1 DM) diets were formulated: one fish meal‐based diet integrated with fish oil (FMO) and two 40% Spirulina meal‐based diets integrated with corn (SPC) or soybean (SPS) oils respectively. One hundred and thirty‐five white sturgeon fingerlings (mean weight 17.5 g) were stocked randomly in nine fibreglass tanks. At the end of the trial, which lasted 71 days, the growth performance traits and somatic indexes were determined. The chemical composition, gross energy and FA profile were determined on the fish fillets. No significant effects were observed for the growth performances or fillet chemical composition. The FA profile of the fillets reflected those of the diets. In particular, the fillets of the fish fed with the SPC and SPS diets were lower in n‐3 FA, due to the substitution of fish oil (FO) with POs. It is possible to replace FO and meal in sturgeon; therefore, Spirulina meal integrated with POs could be a good alternative to sturgeon diet. 相似文献
595.
596.
597.
Massimo Genovese Concetta Imperatore Marcello Casertano Anna Aiello Francesco Balestri Lucia Piazza Marialuisa Menna Antonella Del Corso Paolo Paoli 《Marine drugs》2021,19(10)
An in-depth study on the inhibitory mechanism on protein tyrosine phosphatase 1B (PTP1B) and aldose reductase (AR) enzymes, including analysis of the insulin signalling pathway, of phosphoeleganin, a marine-derived phosphorylated polyketide, was achieved. Phosphoeleganin was demonstrated to inhibit both enzymes, acting respectively as a pure non-competitive inhibitor of PTP1B and a mixed-type inhibitor of AR. In addition, in silico docking analyses to evaluate the interaction mode of phosphoeleganin with both enzymes were performed. Interestingly, this study showed that phosphoeleganin is the first example of a dual inhibitor polyketide extracted from a marine invertebrate, and it could be used as a versatile scaffold structure for the synthesis of new designed multiple ligands. 相似文献
598.
The nuclear 28S rRNA and the mitochondrial COII gene were used to establish phylogenetic relationships among species of the family Neanuridae, with special emphasis on species of the subfamily Neanurinae. Phylogenetic analysis was conducted using genetic distances, parsimony and likelihood methods. The D3-D5 fragment of the rRNA gene was very conserved, both in sequence and in secondary structure features. This fragment supplied little information on relationships at this level. The phylogenetic reconstruction based on 1st and 2nd codon positions of the COII gene was partly in accordance with morphological data, but it was discordant for the placement of some species. Relationships among the subfamilies Frieseinae, represented by the Antarctic species Friesea grisea, Pseudachorutinae and Neanurinae were uncertain. The subfamily Neanurinae and its tribes Neanurini and Paleonurini were shown as monophyletic taxa. Relationships between three species of the genus Bilobella were in accordance with morphological and biochemical data. Relationships between genera within the Neanurini were more controversial. In accordance with morphological hypotheses, a basal position of Thaumanura was suggested, but the molecular data placed Neanura muscorum in a derived position, in sharp contrast with morphological evidence. A close relationship was suggested between Deutonura conjuncta, Cansilianura malatestai and Lathriopyga longiseta. The disagreement between molecular and morphological data suggests that one or both data sets might be affected by a certain degree of homoplasy and that these data should be interpreted with caution in phylogenetic reconstructions. 相似文献
599.
600.
Francesco Tafuri Maurizio Patumi Cesare Marucchini Mario Businelli 《Pest management science》1982,13(6):665-669
Gas-chromatographic analyses of extracts of soil samples from plots, treated with a 50% atrazine wettable powder at dose rates of 2 and 4 kg a.i. ha?1, showed the presence of a new atrazine degradation product. This product was isolated, concentrated and purified by column chromatography and high-performance liquid chromatography. The chromatographic properties of this material were identical with those of a product isolated from a 0.02% methanolic solution of 2-amino-4-chloro-6-isopropyl-amino-1,3,5-triazine that had been stored under laboratory conditions. A combined gas-liquid chromatographic/mass spectrometric assay identified the new product in soil as 2-isopropylamino-4-methoxy-6-methylamino-1,3,5-triazine. 相似文献