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51.
Trovato M Vitarelli E Tripepi M Abate A Rizzo P Benedetto V Sciacchitano S Grosso M Barresi G 《Histology and histopathology》2008,23(5):549-554
The expression of the Na/I Symporter (NIS) in the basolateral cell membrane of the thyroid follicular cells is responsible for the active accumulation of iodide within the thyroid gland and for the subsequent biosynthesis of thyroid hormones. However, several tissues, such as salivary glands, breast, stomach, colon, ovary and endometrium, express NIS even if they are unable to organify iodide. In order to investigate a possible role of NIS in the endometrium, we analyzed, by immunochemistry, the expression of NIS in 44 endometrial samples of 20 patients with primary unexplained infertility, 14 fertile women and 10 in postmenopausal. NIS immunostaining was detected in endometrial cells belonging to the majority of sterile, post-menopausal and fertile women. However, the sterile and post-menopausal patients showed a higher percentage of NIS reactive cells compared to the fertile women (60+/-21% and 57+/-18% vs 19+/-9%; p=0.0001). NIS immunostaining was localized on the membrane and cytoplasm of the endometrial cells. We could not find any correlation between endometrial thickness and NIS immunoexpression. Our results indicate that, in the absence of histological markers, a sterile endometrium can be recognized because of the high expressions of NIS. Moreover, NIS expressions, elevated in both sterile and menopause women, is not related to the estrogen levels, but it could be modulated by factors common to the two conditions. In conclusion, we speculate that NIS may play a role in the development of female sterility. 相似文献
52.
Morphological, physiological and molecular characterization of three copper-resistant actinobacterial strains (AB2A, AB3 and AB5A) isolated from copper-polluted sediments of a drainage channel showed that they belonged to the genus Streptomyces. These characteristics plus their distinctive copper resistance phenotypes revealed considerable divergence among the isolates. Highly dissimilar growth patterns and copper removal efficiency were observed for the selected Streptomyces strains grown on minimal medium (MM) added with 0.5 mM of copper sulfate (MM(Cu)). Strain AB2A showed an early mechanism of copper uptake/retention (80% until day 3), followed by a drastic metal efflux process (days 5-7). In contrast, Streptomyces sp. AB3 and AB5A showed only copper retention phenotypes under the same culture conditions. Particularly, Streptomyces sp. AB5A showed a better efficiency in copper removal (94%), although a longer lag phase was observed for this microorganism grown for 7 days in MM(Cu). Cupric reductase activity was detected in both copper-adapted cells and nonadapted cells of all three strains but this activity was up to 100-fold higher in preadapted cells of Streptomyces sp. AB2A. To our knowledge, this is the first time that cupric reductase activity was demonstrated in Streptomyces strains. 相似文献
53.
Colabufo NA Abate C Contino M Inglese C Niso M Berardi F Perrone R 《Bioorganic & medicinal chemistry letters》2008,18(6):1990-1993
PB183, a non-selective sigma receptor ligand displaying high sigma-1 and sigma-2 receptor affinity, was evaluated in prostate tumour cell lines for its suitability as PET radiotracer. The pharmacodynamic and pharmacokinetic properties suggested PB183 as a potential PET radiotracer to visualize prostate adenocarcinoma. 相似文献
54.
Massimo Nepi Chiara Soligo Daniele Nocentini Mariangela Abate Massimo Guarnieri Giampiero Cai Luca Bini Michele Puglia Laura Bianchi Ettore Pacini 《Flora》2012
Nectar is considered a primary alimentary reward for a large variety of pollinators. Recent studies demonstrated that nectar may have other functions in addition to attracting pollinators. Mainly other two functions have been recognized: defense against microbial invasion and post-secretion modification of sugar profile. The floral nectar of Cucurbita pepo L. has been analyzed to confirm the presence of defense proteins, namely xylosidases that were identified by means of a proteomic approach in a previous study. An enzyme assay was also performed that revealed low invertase activity for which the optimal pH was determined. This invertase activity is not able to modify the sugar profile significantly during the short period of anthesis (6 h). The amino acids complement of the nectar of both sexes was also determined. Sixteen of the 20 protein amino acids have been detected. Proline comprises more than 30% of total amino acid content in male and female flowers. Three non-protein amino acids (taurine, β-alanine, and GABA) represent almost one third of the total amino acid content, and of these, GABA is the most abundant (16%). Several biological activities were attributed to these amino acids and further studies are needed to assess their presumed involvement in managing the foraging behavior of insects. More recent studies, including our own, demonstrate that the various functions of nectar are much more complex than previously thought. 相似文献
55.
QTL associated with Fusarium head blight resistance in the soft red winter wheat Ernie 总被引:2,自引:0,他引:2
Liu S Abate ZA Lu H Musket T Davis GL McKendry AL 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,115(3):417-427
Fusarium head blight (FHB), mainly caused by Fusarium graminearum Schwabe [telomorph: Gibberella zeae Schw. (Petch)], is an increasingly important disease of wheat (Triticum aestivum L.). Host-plant resistance provides the best hope for reducing economic losses associated with FHB, but new sources of resistance
are limited. The moderately resistant winter wheat cultivar, Ernie, may provide a source of resistance that differs from Sumai
3 but these genes have not been mapped. Also hindering resistance breeding may be associations of resistance with agronomic
traits such as late maturity that may be undesirable in some production environments. This research was conducted to identify
QTL associated with type II FHB resistance (FHB severity, FHBS), and to determine if they are associated with days to anthesis
(DTA), number of spikelets (NOS), and the presence/absence of awns. Two hundred and forty-three F8 recombinant inbred lines from a cross between the resistant cultivar, Ernie and susceptible parent, MO 94-317 were phenotyped
for type II FHB resistance using point inoculation in the greenhouse during 2002 and 2003. Genetic linkage maps were constructed
using 94 simple sequence repeat (SSR) and 146 amplified fragment length polymorphic (AFLP) markers. Over years four QTL regions
on chromosomes 2B, 3B, 4BL and 5A were consistently associated with FHB resistance. These QTL explained 43.3% of the phenotypic
variation in FHBS. Major QTL conditioning DTA and NOS were identified on chromosome 2D. Neither the QTL associated with DTA
and NOS nor the presence/absence of awns were associated with FHB resistance in Ernie. Our results suggest that the FHB resistance
in Ernie appears to differ from that in Sumai 3, thus pyramiding the QTL in Ernie with those from Sumai 3 could result in
enhanced levels of FHB resistance in wheat. 相似文献
56.
Ana Carolina Muro Emilio Rodríguez Carlos M. Abate Faustino Siñeriz 《Biotechnology letters》2000,22(20):1639-1642
Several levan hyperproducing mutants of Zymomonas mobilis strains were selected by mutagenesis with N-methyl-N-nitro-nitrosoguanidine and caffeine. Highest levan production (41 g l–1) was obtained with a mutant strain HL 29 in a culture medium containing 200 g sucrose l–1 and 0.5 g (NH4)2SO4 l–1 stored at 7 °C for 29 days. This is the first report describing the levan synthesis by Z. mobilis at 7 °C. 相似文献
57.
Enhanced Efficiency and Stability of Perovskite Solar Cells Through Nd‐Doping of Mesostructured TiO2 下载免费PDF全文
Bart Roose Karl C. Gödel Sandeep Pathak Aditya Sadhanala Juan Pablo Correa Baena Bodo D. Wilts Henry J. Snaith Ulrich Wiesner Michael Grätzel Ullrich Steiner Antonio Abate 《Liver Transplantation》2016,6(2)
Block‐copolymer templated chemical solution deposition is used to prepare mesoporous Nd‐doped TiO2 electrodes for perovskite‐based solar cells. X‐ray diffraction and photothermal deflection spectroscopy show substitutional incorporation into the TiO2 crystal lattice for low Nd concentration, and increasing interstitial doping for higher concentrations. Substitutional Nd‐doping leads to an increase in stability and performance of perovskite solar cells by eliminating defects and thus increasing electron transport and reducing charge recombination in the mesoporous TiO2. The optimized doping concentration of 0.3% Nd enables the preparation of perovskite solar cells with stabilized power conversion efficiency of >18%. 相似文献
58.
Previous research on warfare in a worldwide sample of societies by Ember and Ember (Journal of Conflict Resolution, 36, 242–262, 1992a) found a strong relationship between resource unpredictability (particularly food scarcity caused by natural disasters) in nonstate, nonpacified societies and overall warfare frequency. Focusing on eastern Africa, a region frequently plagued with subsistence uncertainty as well as violence, this paper explores the relationships between resource problems, including resource unpredictability, chronic scarcity, and warfare frequencies. It also examines whether resource scarcity predicts more resource-taking in land, movable property, and people, as well as the commission of atrocities. Results support previous worldwide results regarding the relationship between resource unpredictability and warfare frequency. Results regarding resource-taking and atrocities are more nuanced and complex. In almost all findings, relationships are generally in opposite directions in nonstate and state societies. In post-hoc analyses, atrocities are significantly more likely to be committed in states than in nonstates. 相似文献
59.
C. M. Abate D. A. S. Callieri S. Acosta M. de Vié 《World journal of microbiology & biotechnology》1987,3(4):401-409
Summary A flocculentSaccharomyces sp., isolated from spontaneously fermenting sugar-cane juice, was used to produce ethanol in a continuous upflow reactor. Media of different composition were tested using the same fermentation conditions. The best results were obtained fermenting either sugar-cane juice or molasses. The differences observed could be due to the influence of the medium composition on the growth rate and on the expression of the flocculent capacity of the yeast, both factors which modified the cell biomass concentration within the reactor.
Resumen Una cepa floculante deSaccharomyces, aislada de jugo de caña de azúcar, se utilizó para producir etanol fermentando medios de distinta composición en un reactor continuo de flujo ascendente. Los mejores resultados se obtuvieron con jugo de caña de azúcar y con melaza. Las diferencias observadas según el mosto utilizado pueden deberse a la influencia de la composición del medio sobre la velocidad de multiplicación y capacidad foculante de la levadura, modificando de esta manera la concentración de biomasa dentro del reactor.
Résumé Une souche floculante deSaccharomyces isolée du jus de canne à sucre a été utilisée pour produire l'éthanol, dans un réacteur continu à flux ascendant, par fermentation de milieux de culture de différentes compositions. Les meilleurs résultats ont été obtenus avec le jus de canne à sucre et les molasses. Les différences qu'on a vues selon le moût utilisé peuvent être dues à l'influence de la composition du milieu sur la vitesse de multiplication et la capacité floculante de la levure, donnant une modification de la concentration de biomasse dans le réacteur.相似文献
60.
Spencer CT Abate G Blazevic A Hoft DF 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(7):4471-4484
Mycobacterium tuberculosis and Mycobacterium bovis bacillus Calmette-Guérin (BCG) induce potent expansions of human memory Vgamma(9)(+)Vdelta(2)(+) T cells capable of IFN-gamma production, cytolytic activity, and mycobacterial growth inhibition. Certain phosphoantigens expressed by mycobacteria can stimulate gamma(9)delta(2) T cell expansions, suggesting that purified or synthetic forms of these phosphoantigens may be useful alone or as components of new vaccines or immunotherapeutics. However, we show that while mycobacteria-activated gamma(9)delta(2) T cells potently inhibit intracellular mycobacterial growth, phosphoantigen-activated gamma(9)delta(2) T cells fail to inhibit mycobacteria, although both develop similar effector cytokine and cytolytic functional capacities. gamma(9)delta(2) T cells receiving TLR-mediated costimulation during phosphoantigen activation also failed to inhibit mycobacterial growth. We hypothesized that mycobacteria express Ags, other than the previously identified phosphoantigens, that induce protective subsets of gamma(9)delta(2) T cells. Testing this hypothesis, we compared the TCR sequence diversity of gamma(9)delta(2) T cells expanded with BCG-infected vs phosphoantigen-treated dendritic cells. BCG-stimulated gamma(9)delta(2) T cells displayed a more restricted TCR diversity than phosphoantigen-activated gamma(9)delta(2) T cells. In addition, only a subset of phosphoantigen-activated gamma(9)delta(2) T cells functionally responded to mycobacteria-infected dendritic cells. Furthermore, differential inhibitory functions of BCG- and phosphoantigen-activated gamma(9)delta(2) T cells were confirmed at the clonal level and were not due to differences in TCR avidity. Our results demonstrate that BCG infection can activate and expand protective subsets of phosphoantigen-responsive gamma(9)delta(2) T cells, and provide the first indication that gamma(9)delta(2) T cells can develop pathogen specificity similar to alphabeta T cells. Specific targeting of protective gamma(9)delta(2) T cell subsets will be important for future tuberculosis vaccines. 相似文献