1,721,018 research outputs found
Monstrilloids (Crustacea: Copepoda) from the Mediterranean Sea (Northern Adriatic Sea), with a description of six new species
No full textSuárez-Morales, Eduardo, Goruppi, Alenka, de Olazabal, Alessandra, Tirelli, Valentina (2017): Monstrilloids (Crustacea: Copepoda) from the Mediterranean Sea (Northern Adriatic Sea), with a description of six new species. Journal of Natural History (J. Nat. Hist.) 51 (31-32): 1795-1834, DOI: 10.1080/00222933.2017.1359698, URL: http://dx.doi.org/10.1080/00222933.2017.135969
Characterization of human erythroblasts produced in vitro using HEMA culture
No full textIn the context of the constant difficulty of obtaining supplies of blood products, the interest of disposing of complementary sources of red blood cells (RBCs) for transfusion is evident. Thus, an attempt to generate erythroid cells in vitro makes good sense.
We explored in this work the characteristic of in vitro culture of erythroblasts (EBs) expanded from adult peripheral blood (AB) or cord blood (CB) mononuclear cells (MNCs), with the aim to define the best source for EBs amplification and to optimize the culture conditions to reach a clinical grade production of RBCs. With the aim to define the best source for EBs amplification, we studied the progenitor cell content and the amplification potential of AB- and CB-MNCs in the HEMA culture system. First, five distinct cell populations have been identified by CD34/CD36 staining in AB- and CB-MNCs at the beginning of the culture. They were morphologically and functionally (CFC, liquid culture) characterized. As expected, results showed that in CB the CD34pos content was higher than in AB (1.1±0.66 vs 0.14±0.05, p ≤0.05), while the frequency of erythroid colonies recovered in AB was not statistically different from that of CB. These observations inspired us to compare the expansion potential of these two sources. Results demonstrated that both CD34pos and CD34neg were able to generate EBs in culture. The CD34pos population had a greater proliferation potential, but MNCs generated greater number of EBs in culture both for AB and CB. In addition, we found that AB- and CB-MNCs have similar potential to generate erythroid cells in vitro: MNCs from discarded buffy coat of regular blood donations generate number of EBs comparable to those obtained by low volume CB. In order to reach the goal of optimization of EBs expansion, we performed a functional characterization of EBs obtained from AB- or CB-MNCs. First, we identified in AB-EBs the population that sustains the culture: the immature EBs (iEBs, CD36posCD235anegCD117posCD63low) that retain high self-renewal ability and able to generate greater number of EBs when repeatedly sorted from the bulk of culture. The comparison with CB-EBs revealed the presence of a higher percentage of iEBs than AB-EBs, but despite they showed the same antigenic profile, they highlighted distinct biological properties: they did not retain the ability to self-renew and failed to mature when repeatedly sorted. In fact, the phosphoproteomic profiles revealed differential signaling pathway active in AB- and CB-EBs.
In conclusion, these results indicate that in HEMA culture, MNCs are better than CD34pos cells because they generate greater number of EBs. Furthermore, buffy coats from regular blood donations are a rich source of stem/progenitor cells which may have clinical potential and are not inferior to CB in generation of EBs. Moreover a molecular characterization of the signaling pathways activated during erythroid differentiation could be a novel approach to promote EBs expansion or the sequential purification of iEBs could be considered as an additional strategy to increase the expansion of these cells useful as transfusion products
A first molecular insight into the invasive ctenophore Mnemiopsis leidyi in the northern Adriatic sea
No full textMnemiopsis leidyi A. Agassiz, 1865 is an invasive ctenophore that has spread to many areas of the Eurasian seas in recent decades and is one of the 100 most dangerous species in the world. This species was first observed in the northern Adriatic Sea in 2005 and then disappeared until 2016, when its first bloom was recorded. After that, it bloomed every summer in the area, causing severe damage to artisanal fisheries. Given the lack of genetic data for the northern Adriatic, here we compare the genetic diversity and phylogenetic relationships of M. leidyi populations sampled in 2016, 2018 and 2021 on the north-eastern coast of Italy with native populations and those introduced in other basins using two molecular markers: CytB and ITS. The CytB haplotype found in the samples from the northern Adriatic was identical to that found in the Gulf of Mexico and the Black Sea/Mediterranean. ITS analysis revealed 11 alleles, including 8 novel ones. The presence of a panmictic population in the northern Adriatic and the lower genetic variability compared to the native populations suggest that M. leidyi has been introduced into the Adriatic more than once and the species recently expanded in this area
Figure 12. Monstrilla grandis Giesbrecht, 1891 in Monstrilloids (Crustacea: Copepoda) from the Mediterranean Sea (Northern Adriatic Sea), with a description of six new species
No full textFigure 12. Monstrilla grandis Giesbrecht, 1891, female specimen 'A', from Trieste. (a) right antennule with armature; (b) cephalic area showing cuticular ornamentation, lateral view; (c) same, dorsal view; (d) female specimen 'B', cephalic area showing ventral ornamentation; (e) specimen 'A', urosome with fifth legs, ventral view; (f) urosome with fifth legs, lateral view; (g) same, ventral view, fifth legs omitted; (h) fifth leg, ventral view, thumb-like processes arrowed. Scale bars: 100 µm (a, e–g), 50 µm (b–d, h).Published as part of Suárez-Morales, Eduardo, Goruppi, Alenka, de Olazabal, Alessandra & Tirelli, Valentina, 2017, Monstrilloids (Crustacea: Copepoda) from the Mediterranean Sea (Northern Adriatic Sea), with a description of six new species, pp. 1795-1834 in Journal of Natural History (J. Nat. Hist.) 51 (31-32) on page 1828, DOI: 10.1080/00222933.2017.1359698, http://zenodo.org/record/518253
Generation, Characterization, and Count of Fluorescent Extracellular Vesicles
No full textExtracellular vesicles (EVs) are membranous particles released by all cells in the external milieu. Depending on their origin, they are given different names: exosomes are nanovesicles that originate from the endosomal compartment, whereas microvesicles bud from plasma membrane. Both contain molecules that are crucial for the onset and spreading of different pathologies, from neurodegenerative diseases to cancer, and are considered promising disease markers. On the other hand, EVs are often used as therapeutic tools, and can be engineered to carry drugs and chemicals. This chapter describes a method to produce EVs, mainly exosomes, containing the green fluorescent protein (GFP) linked to an exosome anchoring protein (Nefmut). This enables counting and tracing of fluorescent EVs by different methods, including conventional flow cytometry
A cytofluorimetric analysis of a Saccharomyces cerevisiae population cultured in a fed-batch bioreactor
No full text: The yeast Saccharomyces cerevisiae is a reference model system and one of the widely used microorganisms in many biotechnological processes. In industrial yeast applications, combined strategies aim to maximize biomass/product yield, with the fed-batch culture being one of the most frequently used. Flow cytometry (FCM) is widely applied in biotechnological processes and represents a key methodology to monitor cell population dynamics. We propose here an application of FCM in the analysis of yeast cell cycle along the time course of a typical S. cerevisiae fed-batch culture. We used two different dyes, SYTOX Green and SYBR Green, with the aim to better define each stage of cell cycle during S. cerevisiae fed-batch culture. The results provide novel insights in the use of FCM cell cycle analysis for the real-time monitoring of S. cerevisiae bioprocesses
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Multi-marker metabarcoding approach to study mesozooplankton at basin scale
Get PDFZooplankton plays a pivotal role in marine ecosystems and the characterisation of its biodiversity still represents a challenge for marine ecologists. In this study, mesozooplankton composition from 46 samples collected in summer along the western Adriatic Sea, was retrieved by DNA metabarcoding analysis. For the first time, the highly variable fragments of the mtDNA COI and the V9 region of 18S rRNA genes were used in a combined matrix to compile an inventory of mesozooplankton at basin scale. The number of sequences retrieved after quality filtering were 824,148 and 223,273 for COI and 18S (V9), respectively. The taxonomical assignment against reference sequences, using 95% (for COI) and 97% (for 18S) similarity thresholds, recovered 234 taxa. NMDS plots and cluster analysis divided coastal from offshore samples and the most representative species of these clusters were distributed according to the dominant surface current pattern of the Adriatic for the summer period. For selected sampling sites, mesozooplankton species were also identified under a stereo microscope providing insights on the strength and weakness of the two approaches. In addition, DNA metabarcoding was shown to be helpful for the monitoring of non-indigenous marine metazoans and spawning areas of commercial fish species. We defined pros and cons of applying this approach at basin scale and the benefits of combining the datasets from two genetic markers
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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