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51.
52.
Damiano Porcelli Paolo Barsanti Graziano Pesole Corrado Caggese 《BMC evolutionary biology》2007,7(1):215
Background
When orthologous sequences from species distributed throughout an optimal range of divergence times are available, comparative genomics is a powerful tool to address problems such as the identification of the forces that shape gene structure during evolution, although the functional constraints involved may vary in different genes and lineages. 相似文献53.
Piccinini Alexandre Oliveira Mariana Pacheco Silva Mariella Reinol Bett Gabriela Souza Becker Isabel Borges Mendes Talita Farias Salla Daniéle Hendler Silva Larissa Espindola Vilela Thais Ceresér Moraes Fernanda Mendes Moterle Diego Damiani Adriani Paganini Dagostin Lígia Salvan Tietbohl Lariani Tamires Bittencourt João Vitor Silvano Biehl Erica Denicol Tais Luise Bonfante Sandra Regina Andrade Vanessa Moraes Silveira Paulo Cesar Lock Prophiro Josiane Somariva Ferreira Gabriela Kozuchovski Petronilho Fabricia Kanis Luiz Alberto Rezin Gislaine Tezza 《Neurochemical research》2022,47(7):1888-1903
Neurochemical Research - This study aimed to evaluate the effect of Cynara cardunculus leaf ethanol extract on inflammatory and oxidative stress parameters in the hypothalamus, prefrontal cortex,... 相似文献
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Andrea Mondoni Simone Pedrini Giulietta Bernareggi Graziano Rossi Thomas Abeli Robin J. Probert Michele Ghitti Costantino Bonomi Simone Orsenigo 《Annals of botany》2015,116(6):907-916
Background and Aims Glacier foreland plants are highly threatened by global warming. Regeneration from seeds on deglaciated terrain will be crucial for successful migration and survival of these species, and hence a better understanding of the impacts of climate change on seedling recruitment is urgently needed to predict future plant persistence in these environments. This study presents the first field evidence of the impact of climate change on recruitment success of glacier foreland plants.Methods Seeds of eight foreland species were sown on a foreland site at 2500 m a.s.l., and at a site 400 m lower in altitude to simulate a 2·7 °C increase in mean annual temperature. Soil from the site of origin was used to reproduce the natural germination substrate. Recruitment success, temperature and water potential were monitored for 2 years. The response of seed germination to warming was further investigated in the laboratory.Key Results At the glacier foreland site, seedling emergence was low (0 to approx. 40 %) and occurred in summer in all species after seeds had experienced autumn and winter seasons. However, at the warmer site there was a shift from summer to autumn emergence in two species and a significant increase of summer emergence (13–35 % higher) in all species except two. Survival and establishment was possible for 60–75 % of autumn-emerged seedlings and was generally greater under warmer conditions. Early snowmelt in spring caused the main ecological factors enhancing the recruitment success.Conclusions The results suggest that warming will influence the recruitment of glacier foreland species primarily via the extension of the snow-free period in spring, which increases seedling establishment and results in a greater resistance to summer drought and winter extremes. The changes in recruitment success observed here imply that range shifts or changes in abundance are possible in a future warmer climate, but overall success may be dependent on interactions with shifts in other components of the plant community. 相似文献
56.
Tanja?Boti? Darija?C?r Andrea?Anesi Graziano?Guella Kristina?Sep?i? Dorte?Janussen Daniel?Kersken ?eljko?KnezEmail author 《Polar Biology》2015,38(10):1605-1612
The fatty acid composition of marine cold-water sponges of genus Latrunculia, namely Latrunculia bocagei Ridley and Dendy, 1886, and Latrunculia biformis Kirkpatrick, 1907, for which no fatty acid data had been previously reported, has been examined. High levels of long-chain fatty acids (C24–30) with high unsaturation levels (mainly polyunsaturation), and high incidence of branched- and odd-chain fatty acids in sponges are suggested to be partially connected with their specific cell membrane requirements to surmount the negative effects of low temperatures and to enable growth in extreme environments. Furthermore, variations in the fatty acid profile at the species level may reflect variations in compositions or quantities of symbiotic microorganisms that commonly represent up to 60 % of the sponge wet weight. The fatty acid compositions of lipid-rich sponge extracts from five Latrunculia specimens dredged from the Bransfield Strait near the Antarctic Peninsula, were obtained using supercritical carbon dioxide and analyzed using gas chromatography–mass spectrometry–flame ionization detection. Furthermore, the antioxidant activities of these extracts were determined using the photochemiluminescent method. Along with common fatty acids, the chemical analyses revealed very long-chain fatty acids (C22, C24). Differences were seen for the fatty acid levels between both species and different specimens of the same species. The observed differences do not seem connected to the habitat depth of the specimen, but rather indicate the variations within the associated microbiome. Furthermore, these sponge extracts showed antioxidant activities, confirming that they contain lipidic compounds that strongly scavenge free radicals. 相似文献
57.
On the effect of hydrostatic pressure on the conformational stability of globular proteins 下载免费PDF全文
Giuseppe Graziano 《Biopolymers》2015,103(12):711-718
The model developed for cold denaturation (Graziano, PCCP 2010, 12, 14245‐14252) is extended to rationalize the dependence of protein conformational stability upon hydrostatic pressure, at room temperature. A pressure− volume work is associated with the process of cavity creation for the need to enlarge the liquid volume against hydrostatic pressure. This contribution destabilizes the native state that has a molecular volume slightly larger than the denatured state due to voids existing in the protein core. Therefore, there is a hydrostatic pressure value at which the pressure−volume contribution plus the conformational entropy loss of the polypeptide chain are able to overwhelm the stabilizing gain in translational entropy of water molecules, due to the decrease in water accessible surface area upon folding, causing denaturation. © 2015 Wiley Periodicals, Inc. Biopolymers 103: 711–718, 2015. 相似文献
58.
A New Medical Device Rigeneracons Allows to Obtain Viable Micro‐Grafts From Mechanical Disaggregation of Human Tissues 下载免费PDF全文
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Talita A. Sampaio e Silva Adriana Knob Célia R. Tremacoldi Marcia R. Brochetto-Braga Eleonora Cano Carmona 《World journal of microbiology & biotechnology》2011,27(11):2491-2497
Acid proteases represent an important group of enzymes, widely used in food, beverage and pharmaceutical industries. For most
of these applications the enzymatic preparation must be at least partially purified and free of substances that could change
the characteristics of the product or the process. Fungal proteases have replaced other sources because they are easily obtained
mainly from Mucor, Rhizopus, Penicillium
and
Aspergillus species. A strain of Aspergillus
clavatus was selected by producing high level of acid protease activity. An extracellular aspartatic protease from this strain was
purified 37.2 times with 37% recovery using (NH4)2SO4 fractionation and ion-exchange chromatography. The enzyme was found to be monomeric having a molecular mass of 30.4 kDa.
The purified enzyme is an acid protease with optimum pH of 5.5 and temperature for optimum activity of 50 °C. Its high pH
stability was verified in the range of 3.5–6.5. The acid protease was strongly inhibited by Hg+2 and partially inhibited by Cu+2, Zn+2 and Mn+2. The enzyme was sensitive to denaturing agent SDS and activated by thiol-containing reducing agent dithiotreitol (DTT). The
protease activity was not influenced by iodoacetic acid, E-64 and PMSF, while it was lightly actived by EDTA and totally inhibited
by pepstatin, with a Ki of 7.8 μM, indicating that is an aspartic protease. A.
clavatus acid protease presents interesting characteristics for biotechnological process, such as cheese and flavor manufacture and
dietary supplements, in which activity and stability in acid pH are required. 相似文献