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81.
Detection of a Salmonella enterica Serovar California Strain Spreading in Spanish Feed Mills and Genetic Characterization with DNA Microarrays 下载免费PDF全文
Juan Alvarez Steffen Porwollik Idoia Laconcha Vassilis Gisakis Ana Beln Vivanco Iratxe Gonzalez Susana Echenagusia Nieves Zabala Felisa Blackmer Michael McClelland Aitor Rementeria Javier Garaizar 《Applied microbiology》2003,69(12):7531-7534
We performed an epidemiological study on Salmonella isolated from raw plant-based feed in Spanish mills. Overall, 32 different Salmonella serovars were detected. Despite its rare occurrence in humans and animals, Salmonella enterica serovar California was found to be the predominant serovar in Spanish feed mills. Different typing techniques showed that isolates of this serovar were genetically closely related, and comparative genomic hybridization using microarray technology revealed 23 S. enterica serovar Typhimurium LT2 gene clusters that are absent from serovar California. 相似文献
82.
Arantxa Palacín Cristina Gómez-Casado Luis A. Rivas Jacobo Aguirre Leticia Tordesillas Joan Bartra Carlos Blanco Teresa Carrillo Javier Cuesta-Herranz Consolación de Frutos Genoveva García álvarez-Eire Francisco J. Fernández Pedro Gamboa Rosa Mu?oz Rosa Sánchez-Monge Sofía Sirvent María J. Torres Susana Varela-Losada Rosalía Rodríguez Victor Parro Miguel Blanca Gabriel Salcedo Araceli Díaz-Perales 《PloS one》2012,7(12)
The study of cross-reactivity in allergy is key to both understanding. the allergic response of many patients and providing them with a rational treatment In the present study, protein microarrays and a co-sensitization graph approach were used in conjunction with an allergen microarray immunoassay. This enabled us to include a wide number of proteins and a large number of patients, and to study sensitization profiles among members of the LTP family. Fourteen LTPs from the most frequent plant food-induced allergies in the geographical area studied were printed into a microarray specifically designed for this research. 212 patients with fruit allergy and 117 food-tolerant pollen allergic subjects were recruited from seven regions of Spain with different pollen profiles, and their sera were tested with allergen microarray. This approach has proven itself to be a good tool to study cross-reactivity between members of LTP family, and could become a useful strategy to analyze other families of allergens. 相似文献
83.
84.
Antoni Femenia Maria Garcia-Conesa Susana Simal Carmen Rossell 《Carbohydrate polymers》1998,35(3-4):169-177
Loquat fruit (Eriobotrya japonica L. cv. Algor) was dissected to give the following tissue zones: epidermis or epicarp, flesh or mesocarp, integument (a thin layer surrounding the seed cotyledons), seed testa, kernel and hairy receptacle. The alcohol insoluble residues (AIRs) from all these tissues were proved to be free of starch, except loquat kernel which on a fresh weight basis contained about 34% of starch. AIRs were analysed for moisture, ashes, protein, lignin and the component sugars were released by two hydrolytic procedures which helped to distinguish the sugars from non-cellulosic polysaccharides and cellulose. Their major component polysaccharides were inferred to be pectic polysaccharides since all AIRs were very rich in sugars such as uronic acids, arabinose and galactose. Pectic polysaccharides contributed up to 70% of total cell wall polysaccharides in the edible flesh of the loquat fruit. Important differences in the degree of branching, degree of esterification and in the amounts of Ca and Mg associated with pectic polysaccharides were detected among pectic polymers depending on the loquat tissue zone. These compositional and structural differences may be related to the role that these pectic polymers play within the tissues which form the loquat fruit. 相似文献
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86.
We have recently demonstrated the cardioprotective effects of a non-alcoholic extract of Argentinian red wine (RWE) on ischemia-reperfusion injury. The aim of the present study was to assess the relative contribution of four phenolic fractions separated from RWE by liquid/liquid extraction with solvents of decreasing hydrophobicity, to the myocardial protection achieved by the original extract. Isovolumic perfused rat hearts treated with each fraction 10 min before ischemia and the first 10 min of reperfusion were submitted to a 20-min global ischemic period followed by 30 min of reperfusion. The treatment with the fraction rich in polymeric proanthocyanidins (fraction IV = aqueous residue) significantly improved the postischemic recovery of left ventricular developed pressure (LVDP) and +dP/dt (max) (111 +/- 5% and 117 +/- 6% vs 61 +/- 4%, 62 +/- 5% , respectively, detected in control hearts) and abolished the increase of left ventricular end diastolic pressure (LVEDP) (8 +/- 2 mmHg vs 42 +/- 4 mmHg in untreated hearts). However, the fraction rich in anthocyanins (III: butanol) elicited a cardioprotective action weaker than the original extract. On the other hand, the representative of either resveratrol or flavan-3-ols and flavonols (fractions I and II) failed to induce this type of response. LDH release and TBARS concentration were significantly lowered after treatment with fraction IV alone. These data show that the fraction rich in polymeric proanthocyanidins exerts a protective effect against myocardial alterations derived from ischemia and reperfusion comparable to the original RWE. This beneficial effect can be correlated to the ability of that fraction to attenuate the degree of lipid peroxidation. 相似文献
87.
Sensing wetness: a new role for the bacterial flagellum 总被引:17,自引:0,他引:17
88.
Júlia D. Moreira Luisa Knorr Marcelo Ganzella Ana Paula Thomazi Carolina G. de Souza Débora G. de Souza Carolina F. Pitta Tadeu Mello e Souza Susana Wofchuk Elaine Elisabetsky Lúcia Vinadé Marcos L.S. Perry Diogo O. Souza 《Neurochemistry international》2010,56(6-7):753-759
Essential omega-3 polyunsaturated fatty acids (ω3) are crucial to brain development and function, being relevant for behavioral performance. In the present study we examined the influence of dietary ω3 in the development of the glutamatergic system and on behavior parameters in rats. Female rats received isocaloric diets, either with ω3 (ω3 group) or a ω3 deficient diet (D group). In ontogeny experiments of their litters, hippocampal immunocontent of ionotropic NMDA and AMPA glutamatergic receptors subunits (NR2 A\B and GluR1, respectively) and the alpha isoform of the calcium-calmodulin protein kinase type II (αCaMKII) were evaluated. Additionally, hippocampal [3H]glutamate binding and uptake were assessed. Behavioral performance was evaluated when the litters were adult (60 days old), through the open-field, plus-maze, inhibitory avoidance and flinch-jump tasks. The D group showed decreased immunocontent of all proteins analyzed at 02 days of life (P2) in comparison with the ω3 group, although the difference disappeared at 21 days of life (except for αCaMKII, which content normalized at 60 days old). The same pattern was found for [3H]glutamate binding, whereas [3H]glutamate uptake was not affected. The D group also showed memory deficits in the inhibitory avoidance, increased in the exploratory pattern in open-field, and anxiety-like behavior in plus-maze. Taken together, our results suggest that dietary ω3 content is relevant for glutamatergic system development and for behavioral performance in adulthood. The putative correlation among the neurochemical and behavioral alterations caused by dietary ω3 deficiency is discussed. 相似文献
89.
Progesterone neuroprotection in spinal cord trauma involves up-regulation of brain-derived neurotrophic factor in motoneurons 总被引:7,自引:0,他引:7
Gonzalez SL Labombarda F Deniselle MC Mougel A Guennoun R Schumacher M De Nicola AF 《The Journal of steroid biochemistry and molecular biology》2005,94(1-3):143-149
Progesterone (PROG) provides neuroprotection to the injured central and peripheral nervous system. These effects may be due to regulation of myelin synthesis in glial cells and also to direct actions on neuronal function. Both types of cells express classical intracellular PROG receptors (PR), while neurons additionally express the PROG membrane-binding site called 25-Dx. In motoneurons from rats with spinal cord injury (SCI), PROG restores to normal the deficient levels of choline acetyl-transferase and of alpha3 subunit Na,K-ATPase mRNA, while levels of the growth associated protein GAP-43 mRNA are further stimulated. Recent studies suggest that neurotrophins are possible mediators of hormone action, and in agreement with this assumption, PROG treatment of rats with SCI increases the expression of brain-derived neurotrophic factor (BDNF) at both the mRNA and protein levels in ventral horn motoneurons. In situ hybridization (ISH) has shown that SCI reduces BDNF mRNA levels by 50% in spinal motoneurons, while PROG administration to injured rats (4mg/kg/day during 3 days, s.c.) elicits a three-fold increase in grain density. In addition to enhancement of mRNA levels, PROG increases BDNF immunoreactivity in perikaryon and cell processes of motoneurons of the lesioned spinal cord, and also prevents the lesion-induced chromatolytic degeneration of spinal cord motoneurons as determined by Nissl staining. Our findings strongly indicate that motoneurons of the spinal cord are targets of PROG, as confirmed by the expression of PR and the regulation of molecular parameters. PROG enhancement of endogenous neuronal BDNF could provide a trophic environment within the lesioned spinal cord and might be part of the PROG activated-pathways to provide neuroprotection. Thus, PROG treatment constitutes a new approach to sustain neuronal function after injury. 相似文献
90.
Ernest D Benavente Francesc Coll Nick Furnham Ruth McNerney Judith R Glynn Susana Campino Arnab Pain Fady R Mohareb Taane G Clark 《BMC bioinformatics》2015,16(1)