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Mesozooplankton is a key component of the ocean, regulating global processes such as the carbon pump, and ensuring energy transfer from lower to higher trophic levels. Yet, knowledge on mesozooplankton diversity, distribution and connectivity at global scale is still fragmented. To fill this gap, we applied DNA metabarcoding to mesozooplankton samples collected during the Malaspina-2010 circumnavigation expedition across the Atlantic, Indian and Pacific oceans from the surface to bathypelagic depths. We highlight the still scarce knowledge on global mesozooplankton diversity and identify the Indian Ocean and the deep sea as the oceanic regions with the highest proportion of hidden diversity. We report no consistent alpha-diversity patterns for mesozooplankton at a global scale, neither across vertical nor horizontal gradients. However, beta-diversity analysis suggests horizontal and vertical structuring of mesozooplankton communities mostly attributed to turnover and reveals an increase in mesozooplankton beta-diversity with depth, indicating reduced connectivity at deeper layers. Additionally, we identify a water mass type-mediated structuring of mesozooplankton bathypelagic communities instead of an oceanic basin-mediated as observed at upper layers. This suggests limited dispersal at deep ocean layers, most likely due to weaker currents and lower mixing of water mass types, thus reinforcing the importance of oceanic currents and barriers to dispersal in shaping global plankton communities.
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Understanding the symbiotic interaction between Coxiella-like endosymbionts (CLE) and their tick hosts is challenging due to lack of isolates and difficulties in tick functional assays. Here we sequenced the metagenome of a CLE population from wild Rhipicephalus sanguineus ticks (CRs) and compared it to the previously published genome of its close relative, CLE of R. turanicus (CRt). The tick hosts are closely related sympatric species, and their two endosymbiont genomes are highly similar with only minor differences in gene content. Both genomes encode numerous pseudogenes, consistent with an ongoing genome reduction process. In silico flux balance metabolic analysis (FBA) revealed the excess production of L-proline for both genomes, indicating a possible proline transport from Coxiella to the tick. Additionally, both CR genomes encode multiple copies of the proline/betaine transporter, proP gene. Modelling additional Coxiellaceae members including other tick CLE, did not identify proline as an excreted metabolite. Although both CRs and CRt genomes encode intact B vitamin synthesis pathway genes, which are presumed to underlay the mechanism of CLE-tick symbiosis, the FBA analysis indicated no changes for their products. Therefore, this study provides new testable hypotheses for the symbiosis mechanism and a better understanding of CLE genome evolution and diversity.
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Coxiella/genética , Coxiella/fisiologia , Genoma Bacteriano , Filogenia , Simbiose/fisiologia , Carrapatos/microbiologia , Animais , Sequência de Bases , MetagenômicaAssuntos
Placenta , Clampeamento do Cordão Umbilical , Gravidez , Feminino , Humanos , Parto Obstétrico , Cordão Umbilical/cirurgiaRESUMO
BACKGROUND: Delayed cord clamping allows for the passage of blood from the placenta to the baby and reduces the risk of iron deficiency in infancy. To hold the infant for more than 1 min at the level of the vagina (as is presently recommended), on the assumption that gravity affects the volume of placental transfusion, is cumbersome, might result in low compliance, and interferes with immediate contact of the infant with the mother. We aimed to assess whether gravity affects the volume of placental transfusion METHODS: We did a multicentre non-inferiority trial at three university-affiliated hospitals in Argentina. We obtained informed consent from healthy mothers with normal term pregnancies admitted early in labour. Vigorous babies born vaginally were randomly assigned in a 1:1 ratio by computer-generated blocks and sequentially numbered sealed opaque envelopes to be held for 2 min before clamping the umbilical cord, at the level of the vagina (introitus group) or on the mother's abdomen or chest (abdomen group). Newborn babies were weighed immediately after birth and after cord clamping. The primary outcome was the difference in weight (as a proxy of placental transfusion volume). The prespecified non-inferiority margin was 18 g (20%). We used t test and χ(2) test for group comparison, and used a multivariable linear regression analysis to control for covariables. This trial is registered with ClinicalTrials.gov, number NCT01497353. FINDINGS: Between Aug 1, 2011, and Aug 31, 2012, we allocated 274 newborn babies to the introitus group and 272 to the abdomen group. 77 newborn babies in the introitus group and 78 in the abdomen group were ineligible after randomisation (eg, caesarean section, forceps delivery, short umbilical cord or nuchal cord). Mean weight change was 56 g (SD 47, 95% CI 50-63) for 197 babies in the introitus group compared with 53 g (45, 46-59) for 194 babies in the abdomen group, supporting non-inferiority of the two approaches (difference 3 g, 95% CI -5.8 to 12.8; p=0.45). We did not note any serious adverse events during the study. INTERPRETATION: Position of the newborn baby before cord clamping does not seem to affect volume of placental transfusion. Mothers could safely be allowed to hold their baby on their abdomen or chest. This change in practice might increase obstetric compliance with the procedure, enhance maternal-infant bonding, and decrease iron deficiency in infancy. FUNDING: Foundation for Maternal and Child Health (FUNDASAMIN).
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Parto Obstétrico/métodos , Gravitação , Circulação Placentária/fisiologia , Cordão Umbilical/fisiologia , Adulto , Argentina , Constrição , Parto Obstétrico/efeitos adversos , Feminino , Humanos , Gravidez , Fatores de Tempo , Adulto JovemRESUMO
Human natural killer (NK) cells are innate lymphoid cells with capacity to kill tumor cells and virus-infected cells. According to the expression of CD56 and CD16 several NK cell subsets have been identified, a major CD56dimCD16+ subpopulation characterized by higher cytotoxic capacity, two CD56bright subsets (CD16-and CD16+) that represent different maturation stages and the fourth CD56-CD16+ subset that correspond to activated dysfunctional NK cells. Previous studies have shown quantitative changes in the frequency, phenotype and distribution of NK cell subsets depending on CMV-serostatus and age. We have analyzed the expression of NKp30, NKp46 and DNAM-1 NK activating receptors on resting and IL-2 activated NK cells from CMV-seronegative and seropositive healthy young donors and from CMV-seropositive elderly individuals. Our results showed that CMV-serostatus of healthy young donors is associated with phenotypic differences on both CD56bright and CD56dim NK cells with an increase of NKp46 and a decrease of NKp30 expression respectively. A reduced expression of DNAM-1 related to ageing and a lower NKp30 expression associated with CMV-seropositivity were observed. The expression of NKp46 and NKp30 was lower in CD57+ NK cells while the expression of DNAM-1 was increased. In vitro NK cell activation by IL-2 increased the expression of NKp46 and NKp30. In summary, both age and CMV-serostatus influence the expression of these cytotoxicity activating receptors that will have functional consequences. In elderly donors is difficult to isolate age from the effect of chronic CMV infection since in our study all elderly donors were CMV-seropositive. The possibility of modulating the expression of these activating receptors by cytokines such as IL-2 may open new opportunities for improving age-associated deterioration of NK cell function.
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Envelhecimento/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Infecções por Citomegalovirus/imunologia , Interleucina-2/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Receptor 1 Desencadeador da Citotoxicidade Natural/imunologia , Receptor 3 Desencadeador da Citotoxicidade Natural/imunologia , Adulto , Fatores Etários , Idoso , Envelhecimento/sangue , Antígenos de Diferenciação de Linfócitos T/sangue , Estudos de Casos e Controles , Células Cultivadas , Pré-Escolar , Citomegalovirus/imunologia , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/virologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Imunofenotipagem , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/virologia , Masculino , Pessoa de Meia-Idade , Receptor 1 Desencadeador da Citotoxicidade Natural/sangue , Receptor 3 Desencadeador da Citotoxicidade Natural/sangue , Fenótipo , Testes SorológicosRESUMO
Polyunsaturated aldehydes (PUAs) are organic compounds mainly produced by diatoms, after cell wounding. These compounds are increasingly reported as teratogenic for species of grazers and deleterious for phytoplanktonic species, but there is still scarce information regarding concentration ranges and the composition of PUAs in the open ocean. In this study, we analyzed the spatial distribution and the type of aldehydes produced by the large-sized (>10 µm) phytoplankton in the Atlantic Ocean surface. Analyses were conducted on PUAs released after mechanical disruption of the phytoplankton cells, referred to here as potential PUAs (pPUAs). Results show the ubiquitous presence of pPUA in the open ocean, including upwelling areas, as well as oligotrophic gyres. Total pPUA concentrations ranged from zero to 4.18 pmol from cells in 1 L. Identified PUAs were heptadienal, octadienal and decadienal, with heptadienal being the most common (79% of total stations). PUA amount and composition across the Atlantic Ocean was mainly related to the nitrogen:phosphorus ratio, suggesting nutrient-driven mechanisms of PUA production. Extending the range of trophic conditions considered by adding data reported for productive coastal waters, we found a pattern of PUA variation in relation to trophic status.
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Aldeídos/isolamento & purificação , Diatomáceas/metabolismo , Fitoplâncton/metabolismo , Aldeídos/química , Oceano AtlânticoRESUMO
In the original publication [...].
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Treatment for the lethal primary adult brain tumor glioblastoma (GBM) includes the chemotherapy temozolomide (TMZ), but TMZ resistance is common and correlates with promoter methylation of the DNA repair enzyme O-6-methylguanine-DNA methyltransferase (MGMT). To improve treatment of GBMs, including those resistant to TMZ, we explored the potential of targeting dopamine receptor signaling. We found that dopamine receptor 3 (DRD3) is expressed in GBM and is also a previously unexplored target for therapy. We identified novel antagonists of DRD3 that decreased the growth of GBM xenograft-derived neurosphere cultures with minimal toxicity against human astrocytes and/or induced pluripotent stem cell-derived neurons. Among a set of DRD3 antagonists, we identified two compounds, SRI-21979 and SRI-30052, that were brain penetrant and displayed a favorable therapeutic window analysis of The Cancer Genome Atlas data demonstrated that higher levels of DRD3 (but not DRD2 or DRD4) were associated with worse prognosis in primary, MGMT unmethylated tumors. These data suggested that DRD3 antagonists may remain efficacious in TMZ-resistant GBMs. Indeed, SRI-21979, but not haloperidol, significantly reduced the growth of TMZ-resistant GBM cells. Together our data suggest that DRD3 antagonist-based therapies may provide a novel therapeutic option for the treatment of GBM.
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Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/patologia , Receptores de Dopamina D3/antagonistas & inibidores , Temozolomida/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , HumanosRESUMO
Breast cancer is a heterogeneous disease from the histological and molecular expression point of view, and this heterogeneity determines cancer aggressiveness. Store-operated Ca2+ entry (SOCE), a major mechanism for Ca2+ entry in non-excitable cells, is significantly remodeled in cancer cells and plays an important role in the development and support of different cancer hallmarks. The store-operated CRAC (Ca2+ release-activated Ca2+) channels are predominantly comprised of Orai1 but the participation of Orai2 and Orai3 subunits has been reported to modulate the magnitude of Ca2+ responses. Here we provide evidence for a heterogeneous expression of Orai2 among different breast cancer cell lines. In the HER2 and triple negative breast cancer cell lines SKBR3 and BT20, respectively, where the expression of Orai2 was greater, Orai2 modulates the magnitude of SOCE and sustain Ca2+ oscillations in response to carbachol. Interestingly, in these cells Orai2 modulates the activation of NFAT1 and NFAT4 in response to high and low agonist concentrations. Finally, we have found that, in cells with high Orai2 expression, Orai2 knockdown leads to cell cycle arrest at the G0-G1 phase and decreases apoptosis resistance upon cisplatin treatment. Altogether, these findings indicate that, in breast cancer cells with a high Orai2 expression, Orai2 plays a relevant functional role in agonist-evoked Ca2+ signals, cell proliferation and apoptosis resistance.
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The multifaceted roles of metabolism in invasion have been investigated across many cancers. The brain tumor glioblastoma (GBM) is a highly invasive and metabolically plastic tumor with an inevitable recurrence. The neuronal glucose transporter 3 (GLUT3) was previously reported to correlate with poor glioma patient survival and be upregulated in GBM cells to promote therapeutic resistance and survival under restricted glucose conditions. It has been suggested that the increased glucose uptake mediated by GLUT3 elevation promotes survival of circulating tumor cells to facilitate metastasis. Here we suggest a more direct role for GLUT3 in promoting invasion that is not dependent upon changes in cell survival or metabolism. Analysis of glioma datasets demonstrated that GLUT3, but not GLUT1, expression was elevated in invasive disease. In human xenograft derived GBM cells, GLUT3, but not GLUT1, elevation significantly increased invasion in transwell assays, but not growth or migration. Further, there were no changes in glycolytic metabolism that correlated with invasive phenotypes. We identified the GLUT3 C-terminus as mediating invasion: substituting the C-terminus of GLUT1 for that of GLUT3 reduced invasion. RNA-seq analysis indicated changes in extracellular matrix organization in GLUT3 overexpressing cells, including upregulation of osteopontin. Together, our data suggest a role for GLUT3 in increasing tumor cell invasion that is not recapitulated by GLUT1, is separate from its role in metabolism and survival as a glucose transporter, and is likely broadly applicable since GLUT3 expression correlates with metastasis in many solid tumors.
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Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 3/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/patologia , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 3/genética , Humanos , Proteínas do Tecido Nervoso/metabolismo , Osteopontina/metabolismo , RNA-SeqRESUMO
OBJECTIVE: To assess whether oxytocin administered before clamping the umbilical cord modifies the volume of placental transfusion. DESIGN: Randomised controlled trial. METHODS: Mothers of term infants born vigorous by vaginal delivery with informed consent provided in early labour were randomly assigned to oxytocin (10 IU) given intravenously within 15 s of birth (group 1) or after clamping the umbilical cord 3 min after delivery (group 2). Soon after birth, all infants were weighed using a 1 g precision scale and subsequently placed on the mother's abdomen or chest. At 3 min, in both groups, the cord was clamped and cut, and the weight was again obtained. The primary outcome (volume of placental transfusion) was estimated by the difference in weights. RESULTS: 144 patients were included. There were no differences in the primary outcome: infants in group 1 (n=70) gained a mean weight of 85.9 g (SD 48.3), and in group 2 (n=74) 86.7 g (SD 49.6) (p=0.92). No differences were found in secondary outcomes, including newborns' haematocrit and bilirubin concentrations and severe maternal postpartum haemorrhage. On the advice of the Data and Safety Monitoring Committee, the trial was stopped due to futility at 25% of the planned sample size. CONCLUSIONS: When umbilical cord clamping is delayed for 3 min, term newborn infants born vigorous receive a clinically significant placental transfusion which is not modified by the administration of intravenous oxytocin immediately after birth. TRIAL REGISTRATION NUMBER: NCT02618499.
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Constrição , Ocitócicos/administração & dosagem , Ocitocina/administração & dosagem , Circulação Placentária , Período Pós-Parto , Cordão Umbilical , Adulto , Bilirrubina/sangue , Peso ao Nascer , Parto Obstétrico , Feminino , Hematócrito , Maternidades , Humanos , Recém-Nascido , Injeções Intravenosas , Masculino , Hemorragia Pós-Parto/prevenção & controle , Gravidez , Fatores de Tempo , Aumento de PesoRESUMO
This study presents the results of research focused on university teachers' perceptions of the implementation of ECO (Explore, Create, and Offer) methodology. Through teachers´ responses, the objective was to learn about the impact ECO has on both teaching and learning. The sample consists of 22 teachers from four academic fields; they implemented ECO methodology during the 2018-19 academic year with 1,350 undergraduate students and 175 Master's-level students. The participating teachers belong to five universities: Universidad de Sevilla (Spain), Universitat de Barcelona (Spain), Universidade de Vigo (Spain), Universidad de Las Palmas de Gran Canaria (Spain) and Universidad Nacional de La Plata (Argentina). An exploratory and descriptive study was carried out, and the data were gathered from an online survey filled in by the teachers. Twenty-eight cases were obtained, one for each course that was involved in the project. The mean values were analysed by running a Kruskal-Wallis H test and ER2 for the effect size. In addition, the thematic analysis method was used to analyse the teachers' perceptions while representing their opinions faithfully. The results showed that ECO methodology has a very positive effect on the personal development of the teachers. ECO is a methodology that comes to have revolutionary effects, improving the relationship between teachers and students, who strengthen their commitment to their own learning. It is also an excellent means for connecting students with the social and professional world outside of academia.
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Atitude , Educação/métodos , Docentes/psicologia , Modelos Educacionais , Universidades , Argentina , Docentes/estatística & dados numéricos , Humanos , Aprendizagem , Espanha , Estudantes/psicologia , Inquéritos e Questionários/estatística & dados numéricosRESUMO
The evolution of the results of Progress in International Reading Literacy Study in 2006, 2011 and 2016, as well as the difficulties found by teachers implementing the core competences, have led to the need to reflect on new assessment models. The objective of our research was to design a communicative competence assessment model and verify its effect on primary education teachers. The method applied was a focus group study. Participants came from four primary education schools in the province of Seville (Spain). The data were gathered through discussion groups. The COREQ checklist was followed. Qualitative thematic analysis of the data was carried out using Atlas-ti. An inductive coding scheme was established. The results have enabled the construction of a communicative competence assessment model and its application in primary education classrooms with HERACLES. The effects of the assessment model and the computer software were different according to teachers' profiles. On the one hand, teachers open to educational innovation remained positive when facing the systematic and thorough assessment model. On the other hand, teachers less receptive to changes considered the model to be complex and difficult to apply in the classroom. In conclusion, HERACLES had a beneficial effect on communicative competence assessment throughout the curriculum and made teachers aware of the different dimensions of communicative competence (speaking, listening, reading and writing) and discourse levels (genre, macrostructure and microstructure).
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Comunicação , Professores Escolares , Ensino , Feminino , Humanos , Idioma , Aprendizagem , Masculino , Instituições Acadêmicas , Software , EspanhaRESUMO
The complete larval development of Petrolisthes tuberculatus (including two zoeal stages and the megalopa) is described and illustrated in detail for the first time, based on laboratory-reared material. In order to allow the differentiation of specimens from plankton samples, the larval stages of P. tuberculatus are compared with those known for other porcellanid crabs from Chilean waters (Allopetrolisthes angulosus, Petrolisthes granulosus, P. laevigatus and P. violaceus). As expected, this comparison lead to the inclusion of P. tuberculatus within the "sección Porcellanina" together with the other Chilean species of porcellanids.
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Anomuros , Braquiúros , Decápodes , Animais , Chile , LarvaRESUMO
The immunomodulatory functions mediated by melatonin support its use as vaccine adjuvant. Previously, we have demonstrated that melatonin enhances antibody responses in sheep vaccinated against Dichelobacter nodosus. Here, we analyze the effect of melatonin on T and B lymphocyte subsets in peripheral blood of sheep vaccinated against D. nodosus. We also compare the use of melatonin in implants and in injections. Melatonin administration either as implants or by injection produced higher antibody titers against A1 and C serotypes compared to those animals that received only the vaccine. These results support the use of melatonin as an adjuvant in vaccination against D. nodosus. Firstly, melatonin induces higher antibody titer than the vaccine alone, secondly, melatonin increase IgG+ B lymphocytes and CD4+ T lymphocytes in vaccinated sheep. These results suggest that melatonin enhances T CD4 cell activation and subsequently secondary humoral immune responses. Further studies are required to determine the mechanism underlining the immunomodulatory role of melatonin in the context of vaccination.
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Linfócitos B/imunologia , Vacinas Bacterianas/imunologia , Linfócitos T CD4-Positivos/imunologia , Dichelobacter nodosus/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Melatonina/uso terapêutico , Doenças dos Ovinos/imunologia , Adjuvantes Imunológicos/uso terapêutico , Administração Cutânea , Animais , Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/administração & dosagem , Implantes de Medicamento , Feminino , Citometria de Fluxo/veterinária , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Imunogenicidade da Vacina/efeitos dos fármacos , Imunoglobulina G/sangue , Melatonina/administração & dosagem , Distribuição Aleatória , Ovinos , Doenças dos Ovinos/prevenção & controleRESUMO
For most of the family Porcellanidae, which comprises 283 species, larval development remains to be described. Full development has been only described for 52 species, while part of the larval cycle has been described for 45 species. The importance of knowing the complete larval development of a species goes beyond allowing the identification of larval specimens collected in the plankton. Morphological larval data also constitute a support to cladistic techniques used in the establishment of the phylogenetic status (see Hiller et al. 2006, Marco-Herrero et al. 2013). Nevertheless, the literature on the larval development of this family is old and widely dispersed and in many cases it is difficult to collect the available information on a particular taxon. Towards the aim of facilitating future research, all information available on the larval development of porcellanids has been compiled. Following the taxonomic checklist of Porcellanidae proposed by Osawa and McLaughlin (2010), a checklist has been prepared that reflects the current knowledge about larval development of the group including larval stages and the method used to obtain the larvae, together with references. Those species for which the recognised names have been changed according to Osawa and McLaughlin (2010) are indicated.