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951.
Elisa Giuliano 《Plant biosystems》2013,147(3-5):291-292
Abstract Researchs on the stamens of the healty and parasited flovers of Melandrium album. — The author has examined the structure of the stamens filaments in the healthy and parasited flowers of Melandrium album. The structural modifications induced by the mycelial hyphae of Ustilago violacea expecially in such filaments are pointed out. 相似文献
952.
Oriana Maggi Maria Angelova Elisa Lagostina Anna Adele Fabbri Lorenzo Pecoraro 《Plant biosystems》2013,147(1):247-258
A wide range of cold environments exist, with an equally broad variety of fungi and yeasts that have adapted to such environments. These adaptations, which affect membranes, enzymes and other cellular components, such as radical scavenging molecules, display a great potential for exploitation in biotechnology. Alterations have been detected in membrane lipids, with an increase in fatty acid unsaturated bonds that enhance their fluidity. We report new data on the different phospholipid composition in membrane lipids in the same fungal species from both Antarctic and temperate regions. The decrease in temperature causes intracellular oxidative stress by inducing the generation of reactive oxygen species. We report the results of the first analysis of the non-enzymatic antioxidant response and phenolic compound production by an Antarctic strain of Geomyces pannorum. A survey on yeasts from the cryosphere is reported with a focus on their adaptation to a cold environment. Some studies have shown that the number of macrofungi in glacier forefronts rises as deglaciation increases. The survival success of many plants in such areas may be attributed to their mycorrhizal associations. We highlighted the macrofungal biodiversity of some Italian alpine habitats, in which we Inocybe microfastigiata, Laccaria montana and Lactarius salicis-herbaceae were recorded for the first time in Lombardy (Italy). 相似文献
953.
Juliana F. Santos-Gandelman Olinda C. S. Santos Paula V. M. Pontes Cleyton Lage Andrade Elisa Korenblum Guilherme Muricy Marcia Giambiagi-deMarval Marinella S. Laport 《Marine biotechnology (New York, N.Y.)》2013,15(6):668-676
Among 1,236 colony-forming units (CFU) associated with 11 species of marine sponges collected from a Brazilian coast, a total of 100 morphologically different bacterial strains were analyzed. The phylogenetic diversity of the bacterial isolates was assessed by 16S rRNA gene amplification—restriction fragment length polymorphism (RFLP) analysis, using AluI restriction endonuclease. The RFLP fingerprinting resulted in 21 different patterns with good resolution for the identification of the bacterial isolates at the genus level. The genus Bacillus was the most commonly encountered genus, followed by Kocuria. Regarding the relationship between the morphotypes and species of marine sponges, Mycale microsigmatosa presented major diversity, followed by Dragmacidon reticulatum and Polymastia janeirensis. An antibiotic susceptibility profile of the 100 sponge-associated bacterial strains was determined by the disk diffusion method, and we observed a variable resistance profile, with 15 % of the bacteria being multiresistant. In addition, 71 of 100 strains were able to produce biofilm. These 71 strains were divided into 20 strong biofilm producers, 10 moderate biofilm producers, and 41 weak biofilm producers. The plasmid profile of the 100 bacterial strains was analyzed and 38 (38 %) of these samples possessed one or more plasmids. Studies like this are important to increase the information on these associated bacteria found off the coastline of Brazil, a place which has rich biodiversity that is still unknown. 相似文献
954.
Julia D. Romano Sabrina Sonda Emily Bergbower Maria Elisa Smith Isabelle Coppens 《Molecular biology of the cell》2013,24(12):1974-1995
The obligate intracellular protozoan Toxoplasma gondii actively invades mammalian cells and, upon entry, forms its own membrane-bound compartment, named the parasitophorous vacuole (PV). Within the PV, the parasite replicates and scavenges nutrients, including lipids, from host organelles. Although T. gondii can synthesize sphingolipids de novo, it also scavenges these lipids from the host Golgi. How the parasite obtains sphingolipids from the Golgi remains unclear, as the PV avoids fusion with host organelles. In this study, we explore the host Golgi–PV interaction and evaluate the importance of host-derived sphingolipids for parasite growth. We demonstrate that the PV preferentially localizes near the host Golgi early during infection and remains closely associated with this organelle throughout infection. The parasite subverts the structure of the host Golgi, resulting in its fragmentation into numerous ministacks, which surround the PV, and hijacks host Golgi–derived vesicles within the PV. These vesicles, marked with Rab14, Rab30, or Rab43, colocalize with host-derived sphingolipids in the vacuolar space. Scavenged sphingolipids contribute to parasite replication since alterations in host sphingolipid metabolism are detrimental for the parasite''s growth. Thus our results reveal that T. gondii relies on host-derived sphingolipids for its development and scavenges these lipids via Golgi-derived vesicles. 相似文献
955.
Nicolas Collongues Maria C. Alcaro Frédéric Blanc Francesca Barbetti Marie Fleury Elisa Peroni Paolo Rovero Gabrielle Rudolf Francesco Lolli Élisabeth Trifilieff Anna‐Maria Papini Jérôme de Seze 《Journal of peptide science》2013,19(1):25-32
The detection of reactivity against autoantigens plays a crucial role in the diagnosis of autoimmune diseases. However, only a few autoantibodies are known in each disease, and their precise targets are often not precisely defined. In neuromyelitis optica (NMO), an autoimmune disease of the central nervous system, anti‐aquaporin 4 antibodies are currently the only available immunological markers, although they are not detected in 10–50% of patients. Using enzyme‐linked immunosorbent assays, we evaluated the reactivity against 19 structurally defined peptides in 26 NMO sera compared with 21 healthy subjects. We observed increased levels of IgG against myelin basic protein sequence MBP(156–175), pyruvate dehydrogenase sequence PDH(167–186) and CSF114(Glc), the last of these having a possible correlation with onset of inflammatory relapse. These preliminary results may suggest that the aquaporin 4 is not the unique target in NMO and that the study of reactivity against these peptides would be helpful for the diagnosis and follow‐up of the disease. Complementary studies are however warranted to confirm these results. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
956.
Alessandro Borghesi Maria Antonietta Avanzini Francesca Novara Melissa Mantelli Elisa Lenta Valentina Achille Rosa Maria Cerbo Chryssoula Tzialla Stefania Longo Annalisa De Silvestri Luc J.I. Zimmermann Paolo Manzoni Marco Zecca Arsenio Spinillo Rita Maccario Orsetta Zuffardi Mauro Stronati 《Cytotherapy》2013,15(11):1362-1373
Background aimsThe umbilical cord (UC) is a promising source of mesenchymal stromal cells (MSCs). UC-MSCs display very similar in vitro characteristics to bone marrow–MSCs and could represent a valuable alternative for cell-based therapies. However, it is still unclear whether UC-MSCs are prone or not to the acquisition of genomic imbalances during in vitro expansion.MethodsWith the use of array-comparative genomic hybridization, we compared copy number variations of early (P2–P3) and late (>P5) passages of in vitro–expanded UC-MSCs.ResultsIn two of 11 long-term UC-MSCs cultures, we observed the appearance of clones carrying genomic imbalances, which generated genetic mosaicism at intermediate passages. Although still able to reach the senescence phase, the cells carrying the genomic imbalance acquired a proliferative advantage, as demonstrated by the increase in frequency during long-term culture.ConclusionsAltogether, our results suggest that UC-MSC–based clinical protocols should be designed with caution; their clinical use should be preceded by array-comparative genomic hybridization screening for the acquisition of genomic imbalances during in vitro expansion. 相似文献
957.
Henna M Karvonen Siri T Lehtonen Terttu Harju Raija T Sormunen Elisa Lappi-Blanco Johanna M M?kinen Kirsi Laitakari Shirley Johnson Riitta L Kaarteenaho 《Respiratory research》2013,14(1):84
Background
Chronic obstructive pulmonary disease (COPD) is characterized by structural changes in alveoli and airways. Our aim was to analyse the numbers of alpha-smooth muscle actin (α-SMA) positive cells, as a marker of myofibroblasts, in different lung compartments in non-smokers and smokers with normal lung function or COPD.Methods
α-SMA, tenascin-C (Tn-C) and EDA-fibronectin in alveolar level and airways were assayed by immunohistochemistry and quantified by image analysis. Immunohistochemical findings were correlated with clinical data. α-SMA protein was also analysed by Western blotting from fibroblastic cells cultured from peripheral lung of non-smokers, smokers without COPD and smokers with COPD.Results
In many cases, the endings of the detached alveolar walls were widened, the structures of which were named as widened alveolar tips. Widened alveolar tips contained α-SMA positive cells, which were obviously myofibroblasts. There were less alveolar tips containing positive cells for α-SMA in alveoli and α-SMA positive cells in bronchioles in smokers and in COPD compared to non-smokers. The quantity of α-SMA positive cells was increased in bronchi in COPD. Tn-C was elevated in bronchi in COPD and smokers’ lung. The α-SMA protein level was 1.43-fold higher in stromal cells cultured from non-smokers than in those of smokers.Conclusions
Myofibroblasts are localized variably in normal and diseased lung. This indicates that they have roles in both regeneration of lung and pathogenesis of COPD. The widened alveolar tips, these newly characterized histological structures, seemed to be the source of myofibroblasts at the alveolar level. 相似文献958.
Elisa Mutia Buctuanon 《New genetics and society》2013,32(1):25-41
This study examines a contradictory development in the era of globalization wherein country-specific economic and socio-political institutional environment limits the global flow of technological knowledge and information, particularly in the biotechnology sector. International collaborations for developing new biotechnologies has increased significantly in recent years, but these have virtually bypassed firms in developing countries. The international flow of technologies tends to agglomerate in developed economies particularly in the US, where an appropriate mix of economic choices, social regulation and state action fostered institutional environments that facilitated the development and commercialization of biotechnologies. Moreover, with the heightening competition in the global economy, state and firms of developed economies have evolved into a relationship of close partnership. This shows that, far from being irrelevant, the state remains a political entity that structures the innovation system in order to promote the well-being of its firms. This calls for a re-thinking of the role of the state in technological and economic development, particularly among the developing economies. 相似文献
959.
960.
Bergami Elisa Caroselli Erik Vaccari Lisa Corsi Ilaria Semenov Alexander Macali Armando 《Coral reefs (Online)》2021,40(4):1355-1360
Coral Reefs - Larval settlement is a critical step for sessile benthic species such as corals, whose ability to thrive on diverse natural and anthropogenic substrates may lead to a competitive... 相似文献