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Luca Fontanesi Francesca Bertolini Emilio Scotti Giuseppina Schiavo Michela Colombo Paolo Trevisi 《Animal biotechnology》2013,24(2):92-97
The GPR120 gene (also known as FFAR4 or O3FAR1) encodes for a functional omega-3 fatty acid receptor/sensor that mediates potent insulin sensitizing effects by repressing macrophage-induced tissue inflammation. For its functional role, GPR120 could be considered a potential target gene in animal nutrigenetics. In this work we resequenced the porcine GPR120 gene by high throughput Ion Torrent semiconductor sequencing of amplified fragments obtained from 8 DNA pools derived, on the whole, from 153 pigs of different breeds/populations (two Italian Large White pools, Italian Duroc, Italian Landrace, Casertana, Pietrain, Meishan, and wild boars). Three single nucleotide polymorphisms (SNPs), two synonymous substitutions and one in the putative 3′-untranslated region (g.114765469C > T), were identified and their allele frequencies were estimated by sequencing reads count. The g.114765469C > T SNP was also genotyped by PCR-RFLP confirming estimated frequency in Italian Large White pools. Then, this SNP was analyzed in two Italian Large White cohorts using a selective genotyping approach based on extreme and divergent pigs for back fat thickness (BFT) estimated breeding value (EBV) and average daily gain (ADG) EBV. Significant differences of allele and genotype frequencies distribution was observed between the extreme ADG-EBV groups (P < 0.001) whereas this marker was not associated with BFT-EBV. 相似文献
74.
Livia G. R. P. Macêdo Milena Carvalho-Silva Gabriela K. Ferreira Júlia S. Vieira Natália Olegário Renata C. Gonçalves Francieli S. Vuolo Gustavo C. Ferreira Patrícia F. Schuck Felipe Dal-Pizzol Emilio L. Streck 《Neurochemical research》2013,38(12):2625-2630
Tyrosinemia type II, also known as Richner–Hanhart syndrome, is an autosomal recessive inborn error of metabolism caused by a deficiency of hepatic cytosolic tyrosine aminotransferase, and is associated with neurologic and development difficulties in numerous patients. Considering that the mechanisms underlying the neurological dysfunction in hypertyrosinemic patients are poorly known and that studies demonstrated that high concentrations of tyrosine provoke oxidative stress in vitro and in vivo in the cerebral cortex of rats, in the present study we investigate the oxidative stress parameters (enzymatic antioxidant defenses, thiobarbituric acid-reactive substances and protein carbonyl content) in cerebellum, hippocampus and striatum of 30-old-day rats after acute administration of l-tyrosine. Our results demonstrated that the acute administration of l-tyrosine increased the thiobarbituric acid reactive species levels in hippocampus and the carbonyl levels in cerebellum, hippocampus and striatum. In addition, acute administration of l-tyrosine significantly decreased superoxide dismutase activity in cerebellum, hippocampus and striatum, while catalase was increased in striatum. In conclusion, the oxidative stress may contribute, along with other mechanisms, to the neurological dysfunction characteristic of hypertyrosinemia and the administration of antioxidants may be considered as a potential adjuvant therapy for tyrosinemia, especially type II. 相似文献
75.
Badosa E Ferre R Planas M Feliu L Besalú E Cabrefiga J Bardají E Montesinos E 《Peptides》2007,28(12):2276-2285
A 125-member library of synthetic linear undecapeptides was prepared based on a previously described peptide H-K1KLFKKILKF10L-NH2 (BP76) that inhibited in vitro growth of the plant pathogenic bacteria Erwinia amylovora, Xanthomonas axonopodis pv. vesicatoria, and Pseudomonas syringae pv. syringae at low micromolar concentrations. Peptides were designed using a combinatorial chemistry approach by incorporating amino acids possessing various degrees of hydrophobicity and hydrophilicity at positions 1 and 10 and by varying the N-terminus. Library screening for in vitro growth inhibition identified 27, 40 and 113 sequences with MIC values below 7.5 μM against E. amylovora, P. syringae and X. axonopodis, respectively. Cytotoxicity, bactericidal activity and stability towards protease degradation of the most active peptides were also determined. Seven peptides with a good balance between antibacterial and hemolytic activities were identified. Several analogues displayed a bactericidal effect and low susceptibility to protease degradation. The most promising peptides were tested in vivo by evaluating their preventive effect of inhibition of E. amylovora infection in detached apple and pear flowers. The peptide H-KKLFKKILKYL-NH2 (BP100) showed efficacies in flowers of 63–76% at 100 μM, being more potent than BP76 and only less effective than streptomycin, currently used for fire blight control. 相似文献
76.
Endophytes are fungi that cause asymptomatic infections in leaves and stems of healthy plants. This study evaluated the presence of endophytic fungi on leaves of Rosa hybrida collected in Bogota, (Colombia) using histological techniques and light microscopy. Histological preparations showed fungal mycelium with few cells in the vascular tissue. Colonization of mesophyll cells was not observed. Visualization of fungal cells within plant tissues is a confirmatory test of the endophytic habitat of fungi isolated from leaves of Rosa hybrida. 相似文献
77.
Background
The dispersal ability of queens is central to understanding ant life-history evolution, and plays a fundamental role in ant population and community dynamics, the maintenance of genetic diversity, and the spread of invasive ants. In tropical ecosystems, species from over 40 genera of ants establish colonies in the stems, hollow thorns, or leaf pouches of specialized plants. However, little is known about the relative dispersal ability of queens competing for access to the same host plants.Methodology/Principal Findings
We used empirical data and inverse modeling—a technique developed by plant ecologists to model seed dispersal—to quantify and compare the dispersal kernels of queens from three Amazonian ant species that compete for access to host-plants. We found that the modal colonization distance of queens varied 8-fold, with the generalist ant species (Crematogaster laevis) having a greater modal distance than two specialists (Pheidole minutula, Azteca sp.) that use the same host-plants. However, our results also suggest that queens of Azteca sp. have maximal distances that are four-sixteen times greater than those of its competitors.Conclusions/Significance
We found large differences between ant species in both the modal and maximal distance ant queens disperse to find vacant seedlings used to found new colonies. These differences could result from interspecific differences in queen body size, and hence wing musculature, or because queens differ in their ability to identify potential host plants while in flight. Our results provide support for one of the necessary conditions underlying several of the hypothesized mechanisms promoting coexistence in tropical plant-ants. They also suggest that for some ant species limited dispersal capability could pose a significant barrier to the rescue of populations in isolated forest fragments. Finally, we demonstrate that inverse models parameterized with field data are an excellent means of quantifying the dispersal of ant queens. 相似文献78.
79.
Carlota Barañano Emilio Fernández Gonzalo Méndez Jesús S. Troncoso 《Marine Biology Research》2017,13(9):955-966
The consequences of physical disturbances to seagrasses depend on disturbance frequency relative to the capacity for recolonization and recovery following fragmentation. In a subtidal seagrass meadow of Zostera marina L., following a season of clam harvesting, we compared the temporal change of shoot density and biomass of this seagrass together with the community structure of the associated macroinvertebrates, at two sites differing in the intensity of the physical disturbance. The impacted site showed significantly lower shoot density and total biomass than the non-impacted site initially. The increase in above-ground biomass over four months (May to September) of this species was significantly higher (46%) at the impacted site than in the area not affected by the disturbance. Four months after cessation of the extraction activity, the biomass and density values of Z. marina reached similar values to those measured in the non-impacted site. The sexual reproductive effort of the seagrass population affected by the disturbance (4%) was significantly lower than at the non-impacted site (10%), which could influence genetic diversity and the seed bank. The community structure of molluscs showed 54% similarity between sites at the beginning of the study. Four months later, mollusc communities increased to a similarity of 74%. The current closure season (four months annually) established for the recovery of the exploited stocks of bivalves allowed the recovery of Z. marina density and biomass. Nevertheless, other population properties, such as those related to reproductive patterns, remained altered by the disturbance. 相似文献
80.
Kuschnir E 《Regulatory peptides》2005,128(3):221-225
Hemodynamic patterns in hypertensive patients by radionuclide techniques and tomographic gamma camera were evaluated. In younger hypertensive patients, the hyperkinetic state reflected an increase in heart rate and, consequently, an increased cardiac index and left ventricular ejection fraction (LVEF). Older hypertensive patients, however, showed a different hemodynamic pattern, with reduced systolic and diastolic function at rest compared with normotensive elderly people, and marked depression of cardiac systolic and diastolic reserve during exercise. They also showed strikingly higher hyperresistance and reduced peripheral perfusion. These hemodynamic differences need to be taken into account when considering antihypertensive treatment. In a study in 106 elderly hypertensive patients, treatment with four different antihypertensive drugs produced a significant decrease in total peripheral resistance and blood pressure, together with a reduction in left ventricular (LV) afterload and an increase in cardiac output and LVEF (tending towards normal values). The LV peak filling rate was also increased and evaluation of systolic and diastolic cardiac reserve during exercise showed positive changes in cardiac performance. Left ventricular hyperthropy (LVH) is a powerful predictor of cardiac events. Long-term increases in BP predispose to LVH, impaired diastolic relaxation and, ultimately, ventricular dysfunction. A reduction in LVH produces a number of different beneficial effects. Coronary flow reserve was evaluated in hypertensive patients. Coronary flow reserve was highly impaired in comparison with normotensive controls, and increases in arteriolar wall thickness, collagen content and diastolic dysfunction were also noted. A marked improvement in coronary flow reserve in patients who received antihypertensive therapy was confirmed. 相似文献