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1.
Vox Sang ; 119(4): 377-382, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38226545

RESUMO

BACKGROUND AND OBJECTIVES: Mixed-field agglutination in ABO phenotyping (A3, B3) has been linked to genetically different blood cell populations such as in chimerism, or to rare variants in either ABO exon 7 or regulatory regions. Clarification of such cases is challenging and would greatly benefit from sequencing technologies that allow resolving full-gene haplotypes at high resolution. MATERIALS AND METHODS: We used long-read sequencing by Oxford Nanopore Technologies to sequence the entire ABO gene, amplified in two overlapping long-range PCR fragments, in a blood donor presented with A3B phenotype. Confirmation analyses were carried out by Sanger sequencing and included samples from other family members. RESULTS: Our data revealed a novel heterozygous g.10924C>A variant on the ABO*A allele located in the transcription factor binding site for RUNX1 in intron 1 (+5.8 kb site). Inheritance was shown by the results of the donor's mother, who shared the novel variant and the anti-A specific mixed-field agglutination. CONCLUSION: We discovered a regulatory variant in the 8-bp RUNX1 motif of ABO, which extends current knowledge of three other variants affecting the same motif and also leading to A3 or B3 phenotypes. Overall, long-range PCR combined with nanopore sequencing proved powerful and showed great potential as an emerging strategy for resolving cases with cryptic ABO phenotypes.


Assuntos
Sistema ABO de Grupos Sanguíneos , Subunidade alfa 2 de Fator de Ligação ao Core , Humanos , Íntrons/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Fenótipo , Alelos , Sítios de Ligação , Sistema ABO de Grupos Sanguíneos/genética , Genótipo
2.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34789572

RESUMO

We present experimental evidence of the impact of playing a game on real-life cooperation. The game was framed as a pest-management activity, the effectiveness of which depends on the decisions of others. Playing the game changes behavior in the field, increasing the participation in all collective activities directed at reducing pest pressure. The economic impact of those activities is important, leading to losses that are ∼20% lower than in the control group. Increased cooperation reflects changes in the understanding of others' willingness to cooperate, not changes in the understanding of underlying technological interdependencies.

4.
Nano Lett ; 21(21): 8952-8959, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34723554

RESUMO

The pursuit of miniaturized optical sources for on-chip applications has led to the development of surface plasmon polariton lasers (plasmonic lasers). While applications in spectroscopy and information technology would greatly benefit from the facile and active tuning of the output wavelength from such devices, this topic remains underexplored. Here, we demonstrate optically controlled switching between predefined wavelengths within a plasmonic microlaser. After fabricating Fabry-Pérot plasmonic cavities that consist of two curved block reflectors on an ultrasmooth flat Ag surface, we deposit a thin film of CdSe/CdxZn1-xS/ZnS colloidal core/shell/shell nanoplatelets (NPLs) as the gain medium. Our cavity geometry allows the spatial and energetic separation of transverse modes. By spatially modulating the gain profile within this device, we demonstrate active selection and switching between four transverse modes within a single plasmonic laser. The fast buildup and decay of the plasmonic modes promises picosecond switching times, given sufficiently rapid changes in the structured illumination.

5.
J Environ Manage ; 303: 114131, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34838379

RESUMO

The management of agroecosystems affects biodiversity at all levels from genetic to food-web complexity. Low-input farming systems support higher levels of genetic, species and habitat diversity than high-input, industrial ones. In Greece, as in other Mediterranean countries, the role of traditional farming practices has been underlined in studies concerning conservation in agricultural landscapes. With this study, we aim to provide evidence for the potential of semi-extensive farming for biodiversity conservation at landscape-scale, focusing on Lemnos, a medium-sized island in the North Aegean. Evidence was gathered by species- and community-level local-scale surveys on various trophic levels (vascular plants, arthropods, birds). The surveys took place in 2018 and 2019 in 25 sampling areas comprising 106 plots of 100 m2 (vascular plants, arthropods) and 57 points where bird species were recorded. The plots were classified into three landscape types: mosaic agriculture, mixed rangelands and uniform rangelands. The relevés of Lemnos farmlands were assigned to plant communities of 18 phytosociological alliances, grouped into 12 classes. The most abundant arthropods were Coleoptera, Chilopoda, and Hymenoptera, followed by Opiliones and Isopoda, while 133 different bird species were recorded in total, including the recording for the first time on the island of five species. Farming on Lemnos is rather extensive compared to most agricultural landscapes of Europe. Our approach has demonstrated that, given the geographic characteristics of the area, the measured data reveal very high biodiversity. Our explorative findings suggest that moderate seasonal grazing, the mixed habitat mosaic with ecotones, fallow and stubble fields at the landscape scale, and the small size of fields, the kinds of crop, and farm-scale crop diversification, like mixed cultivation and crop rotation, are key practices supporting this diversity. These explorative findings are considered as a first step providing the baseline for future assessments. A wider effort, for systematic evaluation of the impacts of farming practices to biodiversity, is required, as part of a subsidized agri-environmental scheme and/or through a market-oriented product certification system for the area.


Assuntos
Agricultura , Biodiversidade , Animais , Ecossistema , Fazendas , Grécia
6.
J Phys Chem A ; 125(36): 8132-8139, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34488342

RESUMO

Many chiroptical spectroscopic techniques have been developed to detect chirality in molecular species and probe its role in biological processes. Raman optical activity (ROA) should be one of the most powerful methods, as ROA yields vibrational and chirality information simultaneously and can measure analytes in aqueous and biologically relevant solvents. However, despite its promise, the use of ROA has been limited, largely due to challenges in instrumentation. Here, we report a new approach to ROA that exploits high-frequency polarization modulation. High-frequency polarization modulation, usually implemented with a photoelastic modulator (PEM), has long been the standard technique in other chiroptical spectroscopies. Unfortunately, the need for simultaneous spectral and polarization resolution has precluded the use of PEMs in ROA instruments. We combine a specialized camera system (the Zurich imaging polarimeter, or ZIMPOL) with PEM modulation to perform ROA measurements. We demonstrate performance similar to the current standard in ROA instrumentation while reducing complexity and polarization artifacts. This development should aid researchers in exploiting the full potential of ROA for chemical and biological analysis.

7.
J Proteome Res ; 19(1): 194-203, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31657576

RESUMO

Juvenile myelomonocytic leukemia (JMML) is an aggressive myeloproliferative neoplasm of early childhood with a poor survival rate, thus there is a requirement for improved treatment strategies. Induced pluripotent stem cells offer the ability to model disease and develop new treatment strategies. JMML is frequently associated with mutations in PTPN11. Children with Noonan syndrome, a development disorder, have an increased incidence of JMML associated with specific germline mutations in PTPN11. We undertook a proteomic assessment of myeloid cells derived from induced pluripotent stem cells obtained from Noonan syndrome patients with PTPN11 mutations, either associated or not associated with an increased incidence of JMML. We report that the proteomic perturbations induced by the leukemia-associated PTPN11 mutations are associated with TP53 and NF-Kκb signaling. We have previously shown that MYC is involved in the differential gene expression observed in Noonan syndrome patients associated with an increased incidence of JMML. Thus, we employed drugs to target these pathways and demonstrate differential effects on clonogenic hematopoietic cells derived from Noonan syndrome patients, who develop JMML and those who do not. Further, we demonstrated these small molecular inhibitors, JQ1 and CBL0137, preferentially extinguish primitive hematopoietic cells from sporadic JMML patients as opposed to cells from healthy individuals.


Assuntos
Células-Tronco Pluripotentes Induzidas , Leucemia Mielomonocítica Juvenil , Síndrome de Noonan , Criança , Pré-Escolar , Humanos , Leucemia Mielomonocítica Juvenil/tratamento farmacológico , Leucemia Mielomonocítica Juvenil/genética , Mutação , Proteômica
8.
Mol Biol Rep ; 47(10): 8293-8300, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32979164

RESUMO

Aberrantly high expression of EVI1 in acute myeloid leukaemia (AML) is associated with poor prognosis. For targeted treatment of EVI1 overexpressing AML a more detailed understanding of aspects of spatiotemporal interaction dynamics of the EVI1 protein is important. EVI1 overexpressing SB1690CB AML cells were used for quantification and protein interaction studies of EVI1 and ΔEVI1. Cells were cell cycle-synchronised by mimosine and nocodazole treatment and expression of EVI1 and related proteins assessed by western blot, immunoprecipitation and immunofluorescence. EVI1 protein levels oscillate through the cell cycle, and EVI1 is degraded partly by the proteasome complex. Both EVI1 and ΔEVI1 interact with the co-repressor CtBP1 but dissociate from CtBP1 complexes during mitosis. Furthermore, a large fraction of EVI1, but not ΔEVI1 or CtBP1, resides in the nuclear matrix. In conclusion, EVI1- protein levels and EVI1-CtBP1 interaction dynamics vary though the cell cycle and differ between EVI1 and ΔEVI1. These data ad to the functional characterisation of the EVI1 protein in AML and will be important for the development of targeted therapeutic approaches for EVI1-driven AML.


Assuntos
Oxirredutases do Álcool/biossíntese , Relógios Biológicos , Ciclo Celular , Proteínas de Ligação a DNA/biossíntese , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/metabolismo , Proteína do Locus do Complexo MDS1 e EVI1/biossíntese , Oxirredutases do Álcool/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Humanos , Leucemia Mieloide Aguda/genética , Proteína do Locus do Complexo MDS1 e EVI1/genética
9.
Nucleic Acids Res ; 46(15): 7662-7674, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-29939287

RESUMO

The transcriptional regulator EVI1 has an essential role in early hematopoiesis and development. However, aberrantly high expression of EVI1 has potent oncogenic properties and confers poor prognosis and chemo-resistance in leukemia and solid tumors. To investigate to what extent EVI1 function might be regulated by post-translational modifications we carried out mass spectrometry- and antibody-based analyses and uncovered an ATM-mediated double phosphorylation of EVI1 at the carboxy-terminal S858/S860 SQS motif. In the presence of genotoxic stress EVI1-WT (SQS), but not site mutated EVI1-AQA was able to maintain transcriptional patterns and transformation potency, while under standard conditions carboxy-terminal mutation had no effect. Maintenance of hematopoietic progenitor cell clonogenic potential was profoundly impaired with EVI1-AQA compared with EVI1-WT, in particular in the presence of genotoxic stress. Exploring mechanistic events underlying these observations, we showed that after genotoxic stress EVI1-WT, but not EVI1-AQA increased its level of association with its functionally essential interaction partner CtBP1, implying a role for ATM in regulating EVI1 protein interactions via phosphorylation. This aspect of EVI1 regulation is therapeutically relevant, as chemotherapy-induced genotoxicity might detrimentally sustain EVI1 function via stress response mediated phosphorylation, and ATM-inhibition might be of specific targeted benefit in EVI1-overexpressing malignancies.


Assuntos
Oxirredutases do Álcool/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Autorrenovação Celular/genética , Proteínas de Ligação a DNA/genética , Regulação Leucêmica da Expressão Gênica , Proteína do Locus do Complexo MDS1 e EVI1/genética , Doença Aguda , Oxirredutases do Álcool/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica , Células HEK293 , Humanos , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Proteína do Locus do Complexo MDS1 e EVI1/química , Proteína do Locus do Complexo MDS1 e EVI1/metabolismo , Mutação , Fosforilação
10.
Proc Natl Acad Sci U S A ; 114(44): 11781-11786, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29078271

RESUMO

Declines of marine megafauna due to fisheries by-catch are thought to be mitigated by exclusion devices that release nontarget species. However, exclusion devices may instead conceal negative effects associated with by-catch caused by fisheries (i.e., unobserved or discarded by-catch with low postrelease survival or reproduction). We show that the decline of the endangered New Zealand (NZ) sea lion (Phocarctos hookeri) is linked to latent levels of by-catch occurring in sub-Antarctic trawl fisheries. Exclusion devices have been used since 2001 but have not slowed or reversed population decline. However, 35% of the variability in NZ sea lion pup production is explained by latent by-catch, and the population would increase without this factor. Our results indicate that exclusion devices can obscure rather than alleviate fishery impacts on marine megafauna.


Assuntos
Leões-Marinhos/fisiologia , Animais , Regiões Antárticas , Conservação dos Recursos Naturais/estatística & dados numéricos , Feminino , Pesqueiros/estatística & dados numéricos , Masculino
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