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151.
Collodel G Cardinali R Moretti E Mattioli S Ruggeri S Castellini C 《Theriogenology》2012,77(5):1021-1026
In the present study, the role of rabbit seminal granules was observed. Their influence on motility, capacitation and acrosome reaction, as well as the presence of apoptosis and the morphology of rabbit sperm, were compared in different conditions. Ejaculated sperm from five mature New Zealand White rabbit bucks during three series of collections were studied, comparing raw semen, Percoll-selected sperm and Percoll-selected sperm plus prostate granules. We observed sperm motility kinetic traits by computer-assisted sperm analyzer (CASA) analysis in each sample. Acrosome status was evaluated by FITC-labeled Pisum sativum Agglutinin staining and chlortetracycline fluorescence assay, phosphatidylserine translocation was determined by AnnexinV/Propidium iodide assay and sperm morphology was studied using transmission electron microscopy (TEM). All traits were observed after 30 min incubation at 37 °C in 5% CO2. Data showed that sperm motility and viability markedly improved in the presence of prostate granules, whereas capacitation, acrosome reaction and phosphatidylserine translocation were lowered. TEM confirmed these results. In conclusion, the role of granules was confirmed in synchronizing sperm capacitation and acrosome reaction with egg availability; indeed, rabbit ovulation occurs only 6 to 10 h after mating. 相似文献
152.
Minervini F Di Cagno R Lattanzi A De Angelis M Antonielli L Cardinali G Cappelle S Gobbetti M 《Applied and environmental microbiology》2012,78(4):1251-1264
The study of the microbiotas of 19 Italian sourdoughs used for the manufacture of traditional/typical breads allowed the identification, through a culture-dependent approach, of 20 and 4 species of lactic acid bacteria (LAB) and yeasts, respectively. Numerically, the most frequent LAB isolates were Lactobacillus sanfranciscensis (ca. 28% of the total LAB isolates), Lactobacillus plantarum (ca. 16%), and Lactobacillus paralimentarius (ca. 14%). Saccharomyces cerevisiae was identified in 16 sourdoughs. Candida humilis, Kazachstania barnettii, and Kazachstania exigua were also identified. As shown by principal component analysis (PCA), a correlation was found between the ingredients, especially the type of flour, the microbial community, and the biochemical features of sourdoughs. Triticum durum flours were characterized by the high level of maltose, glucose, fructose, and free amino acids (FAA) correlated with the sole or main presence of obligately heterofermentative LAB, the lowest number of facultatively heterofermentative strains, and the low cell density of yeasts in the mature sourdoughs. This study highlighted, through a comprehensive and comparative approach, the dominant microbiotas of 19 Italian sourdoughs, which determined some of the peculiarities of the resulting traditional/typical Italian breads. 相似文献
153.
Nicla Contran Mariagrazia Tonelli Paolo Crosti Raffaella Cerana Massimo Malerba 《Acta Physiologiae Plantarum》2012,34(2):617-629
Reactive oxygen species (ROS) have pleiotropic effects in plants. ROS can lead to cellular damage and death or play key roles
in control and regulation of biological processes, such as programmed cell death (PCD). This dual role of ROS, as toxic or
signalling molecules, is possible because plant antioxidant system (AS) is able to achieve a tight control over ROS cellular
levels, balancing properly their production and scavenging. AS response in plant PCD has been clearly described only in the
hypersensitive response in incompatible plant–pathogen interactions and in the senescence process and has not been completely
unravelled. In sycamore (Acer pseudoplatanus L.) cultured cells PCD can be induced by Fusicoccin (Fc), Tunicamycin (Tu), and Brefeldin A (Ba). These chemicals induce
comparable PCD time course and extent, while H2O2 production is detectable only in Fc- and, to a lesser extent, in Ba-treated cells. In this paper the AS has been investigated
during PCD of sycamore cells, measuring the effects of the three inducers on the cellular levels of non-enzymatic and enzymatic
antioxidants. Results show that the AS behaviour is different in the PCD induced by the three chemicals. In Fc-treated cells
AS is mainly devoted to decrease the concentration of toxic intracellular H2O2 levels. On the contrary, in cells treated with Tu and Ba, the cell redox state is shifted to a more reduced state and the
enzymatic AS is partially down-regulated, allowing ROS to act as signalling molecules. 相似文献
154.
The draft genome sequence of Lactobacillus rossiae DSM 15814(T) (CS1, ATCC BAA-88) was determined by a whole-genome shotgun approach. Reads were assembled to a 2.9-Mb draft version. RAST genome annotation evidenced 2,723 predicted coding sequences. Many carbohydrate, amino acid, and amino acid derivative subsystem features were found. 相似文献
155.
Lucia Andreini Raffaella Viti Susanna Bartolini David Ruiz José Egea Jose Antonio Campoy 《Trees - Structure and Function》2012,26(3):919-928
Environmental and climatic conditions affect the flower bud growth, flowering and yield performance of fruit species. Temperature
and water availability appear to be important factors for temperate fruit trees in mild climates. The aim of this research
was to study the involvement of temperature regime on biological processes, such as xylem differentiation and dormancy evolution,
in apricot flower buds (Prunus armeniaca L.). Over 3 consecutive years, biological and anatomical investigations were carried out in Tuscany (Italy) and Murcia (Spain)
on two cultivars characterized by a different chilling requirement (CR): Currot, a traditional Spanish cultivar with a very
low CR, and Stark Early Orange (SEO), a North American cultivar with a very high CR. Currot had a regular bearing, and was
characterized by a synchronism between endodormancy release and xylem differentiation. On the other hand, SEO showed an irregular
flower bud growth leading to flowering and fruit-set failure, even with a high level of chilling accumulation. No relationship
was found in SEO between xylem development and flower bud growth reactivation. The de-synchronism between these processes
could determine the poor adaptability to different environmental areas of SEO cultivar, and its very high CR is not the main
hypothesised cause of the altered flower bud development. 相似文献
156.
Tumbarello M Fiori B Trecarichi EM Posteraro P Losito AR De Luca A Sanguinetti M Fadda G Cauda R Posteraro B 《PloS one》2012,7(3):e33705
Background
Very few data exist on risk factors for developing biofilm-forming Candida bloodstream infection (CBSI) or on variables associated with the outcome of patients treated for this infection.Methods and Findings
We identified 207 patients with CBSI, from whom 84 biofilm-forming and 123 non biofilm-forming Candida isolates were recovered. A case-case-control study to identify risk factors and a cohort study to analyze outcomes were conducted. In addition, two sub-groups of case patients were analyzed after matching for age, sex, APACHE III score, and receipt of adequate antifungal therapy. Independent predictors of biofilm-forming CBSI were presence of central venous catheter (odds ratio [OR], 6.44; 95% confidence interval [95% CI], 3.21–12.92) or urinary catheter (OR, 2.40; 95% CI, 1.18–4.91), use of total parenteral nutrition (OR, 5.21; 95% CI, 2.59–10.48), and diabetes mellitus (OR, 4.47; 95% CI, 2.03–9.83). Hospital mortality, post-CBSI hospital length of stay (LOS) (calculated only among survivors), and costs of antifungal therapy were significantly greater among patients infected by biofilm-forming isolates than those infected by non-biofilm-forming isolates. Among biofilm-forming CBSI patients receiving adequate antifungal therapy, those treated with highly active anti-biofilm (HAAB) agents (e.g., caspofungin) had significantly shorter post-CBSI hospital LOS than those treated with non-HAAB antifungal agents (e.g., fluconazole); this difference was confirmed when this analysis was conducted only among survivors. After matching, all the outcomes were still favorable for patients with non-biofilm-forming CBSI. Furthermore, the biofilm-forming CBSI was significantly associated with a matched excess risk for hospital death of 1.77 compared to non-biofilm-forming CBSI.Conclusions
Our data show that biofilm growth by Candida has an adverse impact on clinical and economic outcomes of CBSI. Of note, better outcomes were seen for those CBSI patients who received HAAB antifungal therapy. 相似文献157.
Raffaella Rossi Christine Hale David Goulding Robert Andrews Zarah Abdellah Paul J. Fairchild Gordon Dougan 《PloS one》2012,7(12)
Using an in vitro differentiation protocol we isolated cells with the properties of dendritic cells (DCs) from immunologically refractive pluripotent murine embryonic stem cells (ESCs). These ES-derived dendritic cells (ESDCs) expressed cytokines and were able to present antigen to a T cell line. Infection of ESDCs with Salmonella Typhimurium stimulated the expression of immune cell markers and thousands of murine genes, many associated with the immune response. Consequently, this system provides a novel in vitro model, amenable to genetic modification, for monitoring host/pathogen interactions. 相似文献
158.
159.
Raffaella Ponassi Barbara Biasotti Valeria Tomati Silvia Bruno Alessandro Poggi Davide Malacarne Guido Cimoli Annalisa Salis Sarah Pozzi Maurizio Miglino Gianluca Damonte Pietro Cozzini Francesca Spyrakis Barbara Campanini Luca Bagnasco Nicoletta Castagnino Lorenzo Tortolina Anna Mumot Francesco Frassoni Antonio Daga Michele Cilli Federica Piccardi Ilaria Monfardini Miriam Perugini Gabriele Zoppoli Cristina D’Arrigo Raffaele Pesenti Silvio Parodi 《Cell cycle (Georgetown, Tex.)》2012,11(19):3703
160.