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121.
Danilo Russo 《Mammal Review》2016,46(3):159-159
122.
Margherita Cruciata Ciro Sannino Danilo Ercolini Maria L. Scatassa Francesca De Filippis Isabella Mancuso Antonietta La Storia Giancarlo Moschetti Luca Settanni 《Applied and environmental microbiology》2014,80(7):2050-2061
The microbial composition of artisan and industrial animal rennet pastes was studied by using both culture-dependent and -independent approaches. Pyrosequencing targeting the 16S rRNA gene allowed to identify 361 operational taxonomic units (OTUs) to the genus/species level. Among lactic acid bacteria (LAB), Streptococcus thermophilus and some lactobacilli, mainly Lactobacillus crispatus and Lactobacillus reuteri, were the most abundant species, with differences among the samples. Twelve groups of microorganisms were targeted by viable plate counts revealing a dominance of mesophilic cocci. All rennets were able to acidify ultrahigh-temperature-processed (UHT) milk as shown by pH and total titratable acidity (TTA). Presumptive LAB isolated at the highest dilutions of acidified milks were phenotypically characterized, grouped, differentiated at the strain level by randomly amplified polymorphic DNA (RAPD)-PCR analysis, and subjected to 16S rRNA gene sequencing. Only 18 strains were clearly identified at the species level, as Enterococcus casseliflavus, Enterococcus faecium, Enterococcus faecalis,
Enterococcus lactis, Lactobacillus delbrueckii, and Streptococcus thermophilus, while the other strains, all belonging to the genus Enterococcus, could not be allotted into any previously described species. The phylogenetic analysis showed that these strains might represent different unknown species. All strains were evaluated for their dairy technological performances. All isolates produced diacetyl, and 10 of them produced a rapid pH drop in milk, but only 3 isolates were also autolytic. This work showed that animal rennet pastes can be sources of LAB, mainly enterococci, that might contribute to the microbial diversity associated with dairy productions. 相似文献
123.
Vincenzo Cucinotta Domenico Grasso Giulia Grasso Danilo Milardi 《Nucleosides, nucleotides & nucleic acids》2013,32(10-11):1847-1854
Abstract DSC measurements of binary, decanucleotide/L,L or L,D Ala-Trp, and ternary decanucleotide/L,L or L,D Ala-Trp/Copper(II), systems have been carried out. The results obtained show the different behaviour of the two diastereoisomers both in the binary and in the ternary systems, ascribable to the different disposition of the side-chains in the dipeptides. 相似文献
124.
Luca Cocolin Valentina Alessandria Cristian Botta Roberta Gorra Francesca De Filippis Danilo Ercolini Kalliopi Rantsiou 《PloS one》2013,8(7)
Limited information is available on the impact of the NaOH treatment on table olive fermentations, and for this reason a polyphasic approach has been adopted here to investigate its effect on the fermentation dynamics and bacterial biodiversity. The microbial counts of the main groups involved in the transformation have not shown any differences, apart from a more prompt start of the fermentation when the olives were subjected to the NaOH treatment. The data produced by culture-independent analyses highlighted that the fermentation of table olives not treated with NaOH is the result of the coexistence of two different ecosystems: the surface of the olives and the brines. A sodium hydroxide treatment not only eliminates this difference, but also affects the bacterial ecology of the olives to a great extent. As proved by high-throughput sequencing, the fermentation of the olives not treated with NaOH was characterized by the presence of halophilic bacteria, which were substituted by Lactobacillus at the later stages of the fermentation, while enterobacteria were dominant when the olives were treated with sodium hydroxide. Higher biodiversity was found for Lactobacillus plantarum isolated during untreated fermentation. Different biotypes were found on the olive surface and in the brines. When the debittering process was carried out, a decrease in the number of L. plantarum biotypes were observed and those originating from the surface of the olive did not differentiate from the ones present in the brines. 相似文献
125.
Danilo E. F. L. Fl?res Barbara M. Tomotani Patricia Tachinardi Gisele A. Oda Veronica S. Valentinuzzi 《PloS one》2013,8(7)
Subterranean rodents spend most of the day inside underground tunnels, where there is little daily change in environmental variables. Our observations of tuco-tucos (Ctenomys aff. knighti) in a field enclosure indicated that these animals perceive the aboveground light-dark cycle by several bouts of light-exposure at irregular times during the light hours of the day. To assess whether such light-dark pattern acts as an entraining agent of the circadian clock, we first constructed in laboratory the Phase Response Curve for 1 h light-pulses (1000lux). Its shape is qualitatively similar to other curves reported in the literature and to our knowledge it is the first Phase Response Curve of a subterranean rodent. Computer simulations were performed with a non-linear limit-cycle oscillator subjected to a simple model of the light regimen experienced by tuco-tucos. Results showed that synchronization is achieved even by a simple regimen of a single daily light pulse scattered uniformly along the light hours of the day. Natural entrainment studies benefit from integrated laboratory, field and computational approaches. 相似文献
126.
Ana Paula Junqueira-Kipnis Fábio Muniz de Oliveira Monalisa Martins Trentini Sangeeta Tiwari Bing Chen Danilo Pires Resende Bruna D. S. Silva Mei Chen Lydia Tesfa William R. Jacobs Jr André Kipnis 《PloS one》2013,8(11)
The development of a new vaccine as a substitute for Bacillus Calmette–Guerin or to improve its efficacy is one of the many World Health Organization goals to control tuberculosis. Mycobacterial vectors have been used successfully in the development of vaccines against tuberculosis. To enhance the potential utility of Mycobacterium smegmatis as a vaccine, it was transformed with a recombinant plasmid containing the partial sequences of the genes Ag85c, MPT51, and HspX (CMX) from M. tuberculosis. The newly generated recombinant strain mc2-CMX was tested in a murine model of infection. The recombinant vaccine induced specific IgG1 or IgG2a responses to CMX. CD4+ and CD8+ T cells from the lungs and spleen responded ex vivo to CMX, producing IFN-γ, IL17, TNF-α, and IL2. The vaccine thus induced a significant immune response in mice. Mice vaccinated with mc2-CMX and challenged with M. tuberculosis showed better protection than mice immunized with wild-type M. smegmatis or BCG. To increase the safety and immunogenicity of the CMX antigens, we used a recombinant strain of M. smegmatis, IKE (immune killing evasion), to express CMX. The recombinant vaccine IKE-CMX induced a better protective response than mc2-CMX. The data presented here suggest that the expression of CMX antigens improves the immune response and the protection induced in mice when M. smegmatis is used as vaccine against tuberculosis. 相似文献
127.
128.
Diego Lercari Sebastían Horta Gastón Martínez Danilo Calliari Leandro Bergamino 《Hydrobiologia》2015,742(1):39-58
This article performed a comprehensive assessment of the structure and functioning of the Río de la Plata estuary and adjacent shelf ecosystem, including the effect of fishing. A formerly implemented 37 trophic groups’ mass-balance model (Ecopath) was used to (1) evaluate the particular role of individual biotic components on the ecosystem; (2) characterize the ecosystem in terms of aquatic food web theory; and (3) assess the role of diverse fishing fleets on the ecosystem. Our results indicate a trophic structure and functioning common to other estuaries, where outstanding primary production exceeds consumption, and detritus accumulates in the system. Moreover, our analysis revealed an elevated total system throughput, herbivory outweighing detritivory, and an intermediate state in terms of ecosystem growth and development. Fisheries analyses showed widespread impacts produced by industrial bottom trawl fleets, and specific impacts produced by artisanal fisheries over several groups. Unexpectedly, the evaluation of the effects of fishing showed minor ecosystem consequences by the loss of secondary production and suggests exploitation rates at sustainable levels. This study sets up the basis for temporal ecosystem-level monitoring of the state of the Río de la Plata estuary and adjacent shelf ecosystem. 相似文献
129.
An approach based on the total‐species accumulation curve and higher taxon richness to estimate realistic upper limits in regional species richness
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Stanislao Bevilacqua Karl Inne Ugland Adriana Plicanti Danilo Scuderi Antonio Terlizzi 《Ecology and evolution》2018,8(1):405-415
Most of accumulation curves tend to underestimate species richness, as they do not consider spatial heterogeneity in species distribution, or are structured to provide lower bound estimates and limited extrapolations. The total‐species (T–S) curve allows extrapolations over large areas while taking into account spatial heterogeneity, making this estimator more prone to attempt upper bound estimates of regional species richness. However, the T–S curve may overestimate species richness due to (1) the mismatch among the spatial units used in the accumulation model and the actual units of variation in β‐diversity across the region, (2) small‐scale patchiness, and/or (3) patterns of rarity of species. We propose a new framework allowing the T–S curve to limit overestimation and give an application to a large dataset of marine mollusks spanning over 11 km2 of subtidal bottom (W Mediterranean). As accumulation patterns are closely related across the taxonomic hierarchy up to family level, improvements of the T–S curve leading to more realistic estimates of family richness, that is, not exceeding the maximum number of known families potentially present in the area, can be considered as conducive to more realistic estimates of species richness. Results on real data showed that improvements of the T–S curve to accounts for true variations in β‐diversity within the sampled areas, small‐scale patchiness, and rarity of families led to the most plausible richness when all aspects were considered in the model. Data on simulated communities indicated that in the presence of high heterogeneity, and when the proportion of rare species was not excessive (>2/3), the procedure led to almost unbiased estimates. Our findings highlighted the central role of variations in β‐diversity within the region when attempting to estimate species richness, providing a general framework exploiting the properties of the T–S curve and known family richness to estimate plausible upper bounds in γ‐diversity. 相似文献
130.
Lidiane Maria da Silva-Carvalho Danilo Giovanni Narciso Pastura Jennifer Vieira Gomes Priscyanne Barreto Siqueira Mariana Borges Rodrigues Viviane Moreira de Lima Bruno Pereira Berto 《Systematic parasitology》2018,95(5):455-463
A species of Isospora Schneider, 1881 (Protozoa: Apicomplexa: Eimeriidae) considered as new to science is described and characterised molecularly from the eastern white-throated spadebill Platyrinchus mystaceus Vieillot in the Parque Nacional do Itatiaia, southeastern Brazil. Isospora lopesi n. sp. has oöcysts that are subspheroidal to ovoidal, 18–24 × 18–22 (20.6 × 19.7) µm, with smooth, bilayered wall, c.1.5 μm thick. Micropyle and oöcyst residuum are absent, but one polar granule is present. Sporocysts are ellipsoidal, 12–16 × 8–11 (14.4 × 8.6) µm. The Stieda body is flattened to half-moon-shaped and sub-Stieda body is rounded. Sporocyst residuum is present, consisting of numerous spherules of different sizes. Sporozoites are vermiform with anterior and posterior refractile bodies and nucleus. Molecular analysis was conducted at the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. This new isolate exhibited similarity greater than 98% with Isospora spp. isolates from spectacled warblers Sylvia conspicillata Temminck, 1820. This is the fourth isosporoid coccidian described from New World tyrannid birds, but is the first to have a complementary molecular characterisation. 相似文献