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61.
Gabriella Donà Ivana Ko?uh Anna Maria Brunati Alessandra Andrisani Guido Ambrosini Guglielmo Bonanni Eugenio Ragazzi Decio Armanini Giulio Clari Luciana Bordin 《Marine drugs》2013,11(6):1909-1919
In order to be able to fertilize oocytes, human sperm must undergo a series of morphological and structural alterations, known as capacitation. It has been shown that the production of endogenous sperm reactive oxygen species (ROS) plays a key role in causing cells to undergo a massive acrosome reaction (AR). Astaxanthin (Asta), a photo-protective red pigment belonging to the carotenoid family, is recognized as having anti-oxidant, anti-cancer, anti-diabetic and anti-inflammatory properties and is present in many dietary supplements. This study evaluates the effect of Asta in a capacitating buffer which induces low ROS production and low percentages of acrosome-reacted cells (ARC). Sperm cells were incubated in the presence or absence of increasing concentrations of Asta or diamide (Diam) and analyzed for their ROS production, Tyr-phosphorylation (Tyr-P) pattern and percentages of ARC and non-viable cells (NVC). Results show that Asta ameliorated both sperm head Tyr-P and ARC values without affecting the ROS generation curve, whereas Diam succeeded in enhancing the Tyr-P level but only of the flagellum without increasing ARC values. It is suggested that Asta can be inserted in the membrane and therefore create capacitation-like membrane alteration which allow Tyr-P of the head. Once this has occurred, AR can take place and involves a higher numbers of cells. 相似文献
62.
Magda P��l Vikt��ria Kov��cs Gyula Vida Gabriella Szalai Tibor Janda 《European journal of plant pathology / European Foundation for Plant Pathology》2013,135(1):35-47
Investigations were made on four wheat (Triticum aestivum L.) lines under greenhouse conditions, in order to reveal the role of stress-protective materials, namely salicylic acid, polyamines and antioxidant enzymes in the level of tolerance to powdery mildew infection caused by Blumeria graminis (DC.) Speer f.sp. tritici ém. Marchal. The four lines showed different levels of tolerance, assessed on the Saari-Prescott scoring scale: TC26 and TC33 proved to be susceptible and TC9 and TC19 resistant. In most of the lines, infection caused changes in the activities of antioxidant enzymes, especially in the case of guaiacol peroxidase. Four peroxidase isoenzymes, which responded differently to powdery mildew infection could be detected by gel electrophoresis. Infection had only a slight effect on the levels of salicylic acid (free and bound forms) in inoculated plants; while the levels of polyamines, especially spermidine and spermine increased after infection. Correlation analysis was also performed to examine how close a relationship exists between the parameters investigated. It was concluded that salicylic acid, polyamines and antioxidant enzymes have an important role in plant responses and defence mechanisms during this biotic stress and that in some cases there were significant relationships between them. However the levels of these compounds either initially or after pathogen inoculation, could not explain the degree of tolerance to powdery mildew in the four wheat lines investigated. 相似文献
63.
Gilberto Grandi Maria Gabriella Marchetti Mattia Lanzoni Milvia Chicca 《Fish physiology and biochemistry》2014,40(4):1115-1139
The adenohypophysis was studied by immunocytochemical and ultrastructural methods in juvenile grass carp (Ctenopharyngodon idella) from natural reproduction in Northern Italian rivers. The adenohypophysis included the rostral pars distalis (RPD), the proximal pars distalis (PPD) and the pars intermedia (PI), all deeply penetrated by branches of the neurohypophysis (Nh). The prolactin (PRL), adrenocorticotropic (ACTH), somatotropic (GH), thyrotropic (TSH), gonadotropic type I (GtH I) and type II (GtH II), somatolactin (SL), melanotropic (MSH) and endorphin (END) cells were identified with antisera raised against piscine and human pituitary hormones. In juveniles of 51–69 mm of total body length (TL) with undifferentiated gonads, the PRL cells, arranged in thick strands, occupied most of the RPD. The ACTH and GH cells organized in cords bordering Nh were, respectively, confined to RPD and PPD. The TSH cells were scattered among ACTH cells in RPD and among GH cells in PPD. Cells simultaneously immunoreactive to anti-follicle stimulating hormone and to anti-croaker gonadotropin were intermingled among GH and TSH cells, which were mostly in the dorsal PPD. The SL cells were detected in PI layers bordering the Nh. The MSH and END cells were intermingled in PI and, unlike what observed in other teleosts, their respective antisera did not cross-react. In individuals of 78–112 mm TL with gonads at the beginning of differentiation, the GtH II cells were detected in PPD; all other cell types increased in number. These results, supported by ultrastructural investigations, suggest that SL and GtH II cells are directly involved in gonadal differentiation in C. idella. 相似文献
64.
Dalia Aiello Vladimiro Guarnaccia Alessandro Vitale Gabriella Cirvilleri Giovanni Granata Filomena Epifani Giancarlo Perrone Giancarlo Polizzi Johannes Z. Groenewald Pedro W. Crous 《European journal of plant pathology / European Foundation for Plant Pathology》2014,138(2):347-359
During surveys conducted in 2010–2013, a complete breakage or bending of the trunk and a dry basal stem rot were observed on containerised Brahea armata, B. edulis, Howea forsteriana and Trachycarpus princeps plants in different nurseries located in eastern Sicily (southern Italy). A cylindrocarpon-like species was consistently obtained from diseased palm tissues, while known pathogens of these hosts such as Ganoderma, Phytophthora and Thielaviopsis were not found associated with symptomatic tissues or isolated on standard or selective media. A total of 40 cylindrocarpon-like isolates were collected and characterised based on morphology and DNA phylogeny. Multigene analyses based on the β-tubulin, histone H3, translation elongation factor 1-α, and the internal transcribed spacers (ITS1, 5.8S, ITS2) genes facilitated the identification of a new species, described here as Ilyonectria palmarum. The pathogenicity of one representative isolate collected from each palm species was tested on plants cultivated under nursery conditions and in a growth chamber. All isolates were pathogenic to B. armata, B. edulis, H. forsteriana, and T. princeps and symptoms identical to that observed in nurseries were reproduced. Dry basal stem rot and stem bending caused by Ilyonectria palmarum represents a potentially serious problem for nurseries cultivating containerised palms. 相似文献
65.
Marta De Biaggi Dario Donno Maria Gabriella Mellano Isidoro Riondato Ernest N. Rakotoniaina Gabriele L. Beccaro 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(2):89-94
Interest in new sources of anti-inflammatory and antioxidant compounds has recently become a major research issue, with the cornelian cherry (Cornus mas L.) receiving particular attention for its significant amounts of phenolic compounds and vitamins, which exhibit a wide range of biological and pharmacological properties. This study was aimed at increasing knowledge regarding the cornelian cherry in Italy through the analysis of biologically active substances in the locally available genotype “Chieri”. Spectrophotometric methods were applied to evaluate antioxidant activity, total anthocyanin content and total polyphenolic content. Identification and quantification of the main phytochemical compounds (polyphenols, monoterpenes, organic acids and vitamin C) was performed via high performance liquid chromatography coupled to a diode array detector. C. mas extracts showed high levels of total soluble solids and low acidity. High amounts of phenolic secondary metabolites were observed, with particular reference to anthocyanins (134.71 mgC3G/100 gFW), which confer remarkable nutraceutical properties to the analysed samples. These results highlight the potential of C. mas fruits as a good source of natural antioxidants, suggesting their use as a functional food. Future studies should focus on identifying other specific phytochemical compounds and the genetic traits of local varieties in order to improve cornelian cherry cultivars for food and medicine production. 相似文献
66.
The occurrence of Trabutina mannipara (Hemprich & Ehrenberg, 1829) (Hemiptera: Coccomorpha) is reported for the first time at Linosa (Pelagian Islands, Sicily Channel, Italy) and Libya. T. mannipara was approved by USA authorities for release as biocontrol agent against invasive saltcedars. The potential impact of this species, that in the Mediterranean area showed to be occasionally invasive, is discussed. 相似文献
67.
Stefania Squadrone Maria Cesarina Abete Marco Rizzi Gabriella Monaco Livio Favaro 《Water, air, and soil pollution》2018,229(2):41
The concentrations of trace and non-trace elements were determined in blood and fibers of alpacas (Vicugna pacos) from a north Italian area, as well as in their pasture forages. This is the first investigation regarding this species in Italy, and the first considering alpaca’s fiber as bioindicator worldwide. Metal contents in blood were in the decreasing order: copper?>?zinc?>?aluminum?>?selenium?>?lead?>?nickel?>?manganese?>?chromium?>?arsenic and cadmium, while in fiber, metal levels were in the following order: aluminum?>?zinc?>?copper?>?manganese?>?chromium?>?nickel?>?selenium?>?lead?>?arsenic and cadmium. Antimony, beryllium, mercury, tin, and thallium were below the limit of quantification (0.010 mg kg?1). The analysis of the alpacas’ forage confirmed the same trend found in fiber, suggesting that metal bioaccumulation was affected by diet. These preliminary results have shown that all the trace elements studied bioaccumulated to a greater extent in the fibers of the alpaca than in the blood. Accordingly, we may suggest that alpaca fibers could be used for monitoring exposure especially to non-essential metals like aluminum, cadmium, and lead, and could constitute a suitable non-invasive method for measuring trace and non-trace element exposure in camelids. 相似文献
68.
Characterisation of canine parvovirus strains isolated from cats with feline panleukopenia 总被引:1,自引:0,他引:1
Nicola Decaro Domenico Buonavoglia Francesca Amorisco Antonio Parisi Gabriella Elia Alessandra Cavalli Canio Buonavoglia 《Research in veterinary science》2010,89(2):275-278
Unlike the original canine parvovirus type 2 (CPV-2), CPV-2 variants have gained the ability to replicate in vivo in cats but there is limited information on the disease patterns induced by these variants in the feline host. During 2008, two distinct cases of parvoviral infection were diagnosed in our laboratories. A CPV-2a variant was identified in a 3-month-old Persian kitten displaying clinical sign of feline panleukopenia (FPL) (acute gastroenteritis and marked leukopenia) and oral ulcerations, that died eight days after the onset of the disease. Two pups living in the same pet shop as the cat were found to shed a CPV-2a strain genetically identical to the feline virus and were likely the source of infection. Also, non-fatal infection by a CPV-2c strain occurred in a 2.5-month-old European shorthair kitten displaying non-haemorrhagic diarrhoea and normal white blood cell counts. By sequence analysis of the major capsid protein (VP2) gene, the feline CPV-2c strain showed 100% identity to a recent canine type-2c isolate. Both kittens had been administered multivalent vaccines against common feline pathogens including FPL virus. Whether and to which extent the FPL vaccines can protect cats adequately from the antigenic variants of CPV-2 should be assessed. 相似文献
69.
In this study, polysaccharides of marine origin (agar, alginate and κ-carrageenan) were used to embed nutrients to fabricate biocomposites to be employed in animal feeding. The consistency of biocomposites in water has been evaluated up to 14 days, by several methods: swelling, nutrient release and granulometric analysis. Biocomposites were produced with varying percentages of nutrients (5%–25%) and polysaccharides (1%–2%–3%). All possible biopolymer combinations were tested in order to select those with the best network strength. The best performing biocomposites were those manufactured with agar 2% and nutrients 10%, showing the lowest percentage of water absorption and nutrient release. Biocomposites made of agar 2% and nutrients 10% were the most stable in water and were therefore used to analyze their behavior in water with respect to the release of quercetin, a phenolic compound with demonstrated high antibacterial and antioxidant activities. The leaching of such molecules in water was therefore employed as a further indicator of biocomposite water stability. Altogether, our results confirm the suitability of agar as a binder for biocomposites and provide a positive contribution to aquaculture. 相似文献
70.
Anne Spinosa Domenico Pignone Gabriella Sonnante 《Genetic Resources and Crop Evolution》1998,45(4):347-354
Genetic variation based on isozyme and RAPD analyses was investigated in 47 and 34 accessions respectively of Vigna vexillata from different geographical origins and belonging to three botanical varieties. A total of 9 enzyme systems were studied, accounting for 14 putative loci, 8 of which were polymorphic. The analysis of genetic diversity revealed a low level of within accession variation (HS=0.013), while between accession diversity (DST) was 0.120. Coefficient of gene differentiation (GST) was 0.905, indicating that most variation was among accessions. Nei's genetic distances were calculated on the basis of allelic frequencies and a UPGMA dendrogram was constructed. Twenty arbitrary 10-mer oligonucleotides were used in RAPD analysis. Amplification profiles disclosed a higher level of polymorphism than isozymes. Based on amplification patterns, the similarity index of Jaccard was calculated and a dendrogram constructed on the basis of the similarity matrix. The final clustering based on RAPD data was similar to the one obtained using isozyme allelic frequencies. The classification in botanical varieties did not reflect the allelic constitution of the different samples. On the other hand, referring to geographical origin, most accessions from Africa and from Latin America were distributed respectively in two distinct clusters in the dendrogram. This grouping might also reflect the differences observed in the germination behaviour of V. vexillata from the two continents. 相似文献