1,721,024 research outputs found
SPARTEVs. Characterization of seminal extracellular vesicles subsets used for supplementing in vitro maturation medium of porcine oocytes
No full textResearch on extracellular vesicles (EVs), membrane-delimited nanoparticles (30-to-1000 nm) released by functional cells is currently a challenge for scientific community since they act as essential messengers in pathological and physiological processes, including those related to reproduction. Based on differences in size and biogenesis pathways, EVs released by healthy living cells are classically categorized into exosomes (small EVs) and microvesicles (large EVs). These EVs has been isolated from all reproductive fluids, including seminal plasma (SP), a complex and heterogeneous fluid composed mainly by secretions from accessory sexual glands that accompanies sperm during and after ejaculation. Bearing in mind that SP is beneficial for sperm-oocyte interaction and embryo development and that it contains EVs, which are involved in several sperm functions, the hypothesis of SPARTEVs project was that seminal EVs may play a key role in the in the successful development of the above-mentioned reproductive events. This data set contains the raw data of the characterization of EVs subsets (small (S-EVs) and large (L-EVs)) isolated from pig SP (by a combination of centrifugation, size-exclusion chromatography and ultrafiltration) and used for supplementing in vitro maturation medium of porcine oocytes. The characterization was conducted following MISEV2018 guidelines, and this data set included the raw data obtained from dynamic scattering, nano tracking particle and flow cytometry analyses
SPARTEVs. Gene expression data of cumulus cells in response to seminal extracellular vesicles subsets during in vitro maturation of porcine oocytes
No full textExtracellular vesicles (EVs), nano-sized (30-to-1000 nm) membrane vesicles secreted by all functional cells, are essential intercellular mediators, modulating several physiological and pathological processes. According to their size and biogenic pathway, EVs released by living cells are classically categorized into exosomes (small EVs) and microvesicles (large EVs). EVs has been isolated from all biofluids, including seminal plasma (SP), a fluid composed by secretions from accessory sex glands that accompanies sperm during and after ejaculation. Seminal EVs modulate several sperm physiological processes, and female reproductive tract immune environment, which is required for successful embryo development. Evidence supports that SP may also affect ovarian function. This study evaluated the potential effect of supplementing with two SP-EVs subsets (small (S-EVs) and large (L-EVs)) during in vitro maturation (IVM) of porcine oocytes on gene expression of cumulus cells. Four pathways were investigated using a total of nine genes: i) cell apoptosis using B-cell lymphoma 2 (BCL2) and BCL2 Associated X (BAX); ii) cell proliferation using Cyclin B1 (CCNB1); iii) oocyte maturation through Connexin 43 (CX43), Hyaluronan Synthase 2 (HAS2) and Stearoyl-CoA desaturase 1 (SCD1); and iv) steroidogenesis using Cytochrome P450 Family 11 Subfamily A Member 1 (CYP11A1), Hydroxy-Delta-5-Steroid Dehydrogenase 3 Beta (HSD3B1) and aromatase (CYP19A1). All genes, including housekeeping 60S Ribosomal Protein L18 (RPL19), were selected based on previous literature. The mRNA levels were assessed by quantitative real-time PCR
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Variations on the Author
Full text link“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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Extracellular vesicles in seminal fluid and effects on male reproduction. An overview in farm animals and pets
Full text linkExtracellular vesicles (EVs) are lipid bilayer nanovesicles released by most functional cells to body fluids, containing bioactive molecules, mainly proteins, lipids, and nucleic acids having actions at target cells. The EVs have essential functions in cell-to-cell communication by regulating different biological processes in target cells. Fluids from the male reproductive tract, including seminal plasma, contain many extracellular vesicles (sEVs), which have been evaluated to a lesser extent than those of other body fluids, particularly in farm animals and pets. Results from the few studies that have been conducted indicated epithelial cells of the testis, epididymis, ampulla of ductus deferens and many accessory sex glands release sEVs mainly via apocrine mechanisms. The sEVs are morphologically heterogeneous and bind to functional cells of the male reproductive tract, spermatozoa, and cells of the functional tissues of the female reproductive tract after mating or insemination. The sEVs encapsulate proteins and miRNAs that modulate sperm functions and male fertility. The sEVs, therefore, could be important as reproductive biomarkers in breeding sires. Many of the current findings regarding sEV functions, however, need experimental confirmation. Further studies are particularly needed to characterize both membranes and contents of sEVs, as well as the interaction between sEVs and target cells (spermatozoa and functional cells of the internal female reproductive tract). A priority for conducting these studies is development of methods that can be standardized and that are scalable, cost-effective and time-saving for isolation of different subtypes of EVs present in the entire population of sEVs
Involvement of extracellular vesicle-encapsulated miRNAs in human reproductive disorders: a systematic review
Full text linkIn recent years, extracellular vesicles (EVs) have emerged as essential players in cell-to-cell communication, particularly having an active regulating role in biological systems. Because reproductive-associated processes are not exempt of this communication, multiple studies have been devoted to this realm, focusing on gamete maturation, embryo implantation or fetal development. The aim of the present review was to comprehensively and systematically collect evidence about the function of the microRNA (miRNA) encapsulated in EVs isolated from different reproductive tissues or fluids in reproductive-related diseases. Following PRISMA guidelines, we conducted a systematic search of the literature published in MEDLINE-PubMed until the end of February 2021. After selection, 32 studies were included in the qualitative review comparing the miRNA expression profile in EVs between different pathological disorders. Most reports showed the potential of the miRNAs carried by EVs to be used as putative biomarkers of reproductive disorders, including pregnancy affections, disease progression and quality of preimplantation embryos. The most relevant miRNAs were found to be highly heterogeneous among studies, with some conflicting results. Further research is thus warranted to address whether cofounding factors, such as the methods to isolate EVs and miRNAs, the subset of EVs, the criteria of patient selection, the timing of sample retrieval, or any other factor, may explain the inconsistencies between studies
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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