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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
11.
Transfus Med Hemother ; 47(4): 326-336, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32884505

RESUMO

The U antigen (MNS5) is one of 49 antigens belonging to the MNS blood group system (ISBT002) carried on glycophorins A (GPA) and B (GPB). U is present on the red blood cells in almost all Europeans and Asians but absent in approximately 1.0% of Black Africans. U negativity coincides with negativity for S (MNS3) and s (MNS4) on GPB, thus be called S-s-U-, and is thought to arise from homozygous deletion of GYPB. Little is known about the molecular background of these deletions. Bioinformatic analysis of the 1000 Genomes Project data revealed several candidate regions with apparent deletions in GYPB. Highly specific Gap-PCRs, only resulting in positive amplification from DNAs with deletions present, allowed for the exact genetic localization of 3 different breakpoints; 110.24- and 103.26-kb deletions were proven to be the most frequent in Black Americans and Africans. Among 157 CEPH DNAs, deletions in 6 out of 8 African ethnicities were present. Allele frequencies of the deletions within African ethnicities varied greatly and reached a cumulative 23.3% among the Mbuti Pygmy people from the Congo. Similar observations were made for U+var alleles, known to cause strongly reduced GPB expression. The 110- and 103-kb deletional GYPB haplotypes were found to represent the most prevalent hereditary factors causative of the MNS blood group phenotype S-s-U-. Respective GYPB deletions are now accessible by molecular detection of homo- and hemizygous transmission.

12.
BMC Med Genet ; 19(1): 7, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29325523

RESUMO

BACKGROUND: Fanconi anemia (FA) is an inherited genomic instability disorder with congenital and developmental abnormalities, bone marrow failure and predisposition to cancer early in life, and cellular sensitivity to DNA interstrand crosslinks. CASE PRESENTATION: A fifty-one-year old female patient, initially diagnosed with FA in childhood on the basis of classic features and increased chromosomal breakage, and remarkable sun-sensitivity is described. She only ever had mild haematological abnormalities and no history of malignancy. To identify and characterise the genetic defect in this lady, who is one of the oldest reported FA patients, we used whole-exome sequencing for identification of causative mutations, and functionally characterized the cellular phenotype. Detection of the novel splice site mutation c.793-2A > G and the previously described missense mutation c.1765C > T (p.Arg589Trp) in XPF/ERCC4/FANCQ assign her as the third individual of complementation group FA-Q. Ectopic expression of wildtype, but not mutant, XPF/ERCC4/FANCQ, in patient-derived fibroblasts rescued cellular resistance to DNA interstrand-crosslinking agents. Patient derived FA-Q cells showed impaired nuclear excision repair capacity. However, mutated XPF/ERCC4/FANCQ protein in our patient's cells, as in the two other patients with FA-Q, was detectable on chromatin, in contrast to XP-F cells, where missense-mutant protein failed to properly translocate to the nucleus. CONCLUSIONS: Patients with FA characteristics and UV sensitivity should be tested for mutations in XPF/ERCC4/FANCQ. The missense mutation p.Arg589Trp was previously detected in patients diagnosed with Xeroderma pigmentosum or Cockayne syndrome. Hence, phenotypic manifestations associated with this XPF/ERCC4/ FANCQ mutation are highly variable.


Assuntos
Proteínas de Ligação a DNA/genética , Anemia de Fanconi/genética , Mutação de Sentido Incorreto , Transtornos de Fotossensibilidade/genética , Sequência de Aminoácidos , Linhagem Celular , Linhagem Celular Tumoral , Dano ao DNA , Reparo do DNA , Anemia de Fanconi/diagnóstico , Feminino , Fibroblastos , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Transtornos de Fotossensibilidade/diagnóstico , Sistema Solar
13.
Transfusion ; 58(7): 1752-1762, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29656499

RESUMO

BACKGROUND: Blood group phenotype variation has been attributed to potential resistance to pathogen invasion. Variation was mapped in blood donors from Lampang (northern region) and Saraburi (central region), Thailand, where malaria is endemic. The previously unknown blood group allele profiles were characterized and the data were correlated with phenotypes. The high incidence of the Vel-negative phenotype previously reported in Thais was investigated. STUDY DESIGN AND METHODS: DNA from 396 blood donors was analyzed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry. Outliers were investigated by serology and DNA sequencing. Allele discrimination assays for SMIM1 rs1175550A/G and ACKR1 rs118062001C/T were performed and correlated with antigen expression. RESULTS: All samples were phenotyped for Rh, MNS, and K. Genotyping/phenotyping for RhD, K, and S/s showed 100% concordance. Investigation of three RHCE outliers revealed an e-variant antigen encoded by RHCE*02.22. Screening for rs147357308 (RHCE c.667T) revealed a frequency of 3.3%. MN typing discrepancies in 41 samples revealed glycophorin variants, of which 40 of 41 were due to Mia . Nine samples (2.3%) were heterozygous for FY*01W.01 (c.265C > T), and six samples (1.5%) were heterozygous for JK*02N.01. All samples were wildtype SMIM1 homozygotes with 97% homozygosity for rs1175550A. CONCLUSIONS: Matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry is an efficient method for rapid routine genotyping and investigation of outliers identified novel variation among our samples. The expected high prevalence of the Mi(a+) phenotype was observed from both regions. Of potential clinical relevance in a region where transfusion-dependent thalassemia is common, we identified two RHCE*02 alleles known to encode an e-variant antigen.


Assuntos
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sistema ABO de Grupos Sanguíneos/genética , Antígenos de Grupos Sanguíneos/genética , Citometria de Fluxo , Frequência do Gene/genética , Genótipo , Haplótipos/genética , Humanos , Fenótipo , Polimorfismo Genético/genética , Reação em Cadeia da Polimerase em Tempo Real , Sistema do Grupo Sanguíneo Rh-Hr/genética , Tailândia
14.
Environ Sci Technol ; 52(19): 11151-11160, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30170488

RESUMO

Peat particulate organic matter (POM) is an important terminal electron acceptor for anaerobic respiration in northern peatlands provided that the electron-accepting capacity of POM is periodically restored by oxidation with O2 during peat oxygenation events. We employed push-pull tests with dissolved O2 as reactant to determine pseudo-first-order rate constants of O2 consumption ( kobs) in anoxic peat soil of an unperturbed Swedish ombrotrophic bog. Dissolved O2 was rapidly consumed in anoxic peat with a mean kobs of 2.91 ± 0.60 h-1, corresponding to an O2 half-life of ∼14 min. POM dominated O2 consumption, as evidenced from approximately 50-fold smaller kobs in POM-free control tests. Inhibiting microbial activity with formaldehyde did not appreciably slow O2 consumption, supporting abiotic O2 reduction by POM moieties, not aerobic respiration, as the primary route of O2 consumption. Peat preoxygenation with dissolved O2 lowered kobs in subsequent oxygen consumption tests, consistent with depletion of reduced moieties in POM. Finally, repeated oxygen consumption tests demonstrated that anoxic peat POM has a high reduction capacity, in excess to 20 µmol electrons donated per gram POM. This work demonstrates rapid abiotic oxidation of reduced POM by O2, supporting that short-term oxygenation events can restore the capacity of POM to accept electrons from anaerobic respiration in temporarily anoxic parts of peatlands.


Assuntos
Oxigênio , Solo , Oxirredução , Consumo de Oxigênio , Material Particulado
15.
Pediatr Nephrol ; 33(9): 1547-1551, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29651604

RESUMO

BACKGROUND: Fanconi anaemia (FA) is an inherited disease with bone marrow failure, variable congenital and developmental abnormalities, and cancer predisposition. With improved survival, non-haematological manifestations of FA become increasingly important for long-term management. While renal abnormalities are recognized, detailed data on patterns and frequency and implications for long-term management are sparse. METHODS: We reviewed clinical course and imaging findings of FA patients with respect to renal complications in our centre over a 25-year period to formulate some practical suggestions for guidelines for management of renal problems associated with FA. RESULTS: Thirty patients including four sibling sets were reviewed. On imaging, 14 had evidence of anatomical abnormalities of the kidneys. Two cases with severe phenotype, including renal abnormalities, had chronic kidney disease (CKD) at diagnosis. Haematopoietic stem cell transplantation was complicated by significant acute kidney injury (AKI) in three cases. In three patients, there was CKD at long-term follow-up. All patients had normal blood pressure. CONCLUSIONS: Evaluation of renal anatomy with ultrasound imaging is important at diagnostic workup of FA. While CKD is uncommon at diagnosis, our data suggests that the incidence of CKD increases with age, in particular after haematopoietic stem cell transplantation. Monitoring of renal function is essential for management of FA. Based on these long-term clinical observations, we formulate some practical guidelines for assessment and management of renal abnormalities in FA.


Assuntos
Injúria Renal Aguda/terapia , Anemia de Fanconi/terapia , Rim/anormalidades , Assistência de Longa Duração/normas , Insuficiência Renal Crônica/terapia , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Criança , Pré-Escolar , Progressão da Doença , Anemia de Fanconi/complicações , Anemia de Fanconi/diagnóstico , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Incidência , Lactente , Rim/diagnóstico por imagem , Assistência de Longa Duração/métodos , Masculino , Guias de Prática Clínica como Assunto , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/etiologia , Estudos Retrospectivos , Ultrassonografia
16.
Transfus Med Hemother ; 45(4): 239-250, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30283273

RESUMO

BACKGROUND: High-frequency blood group antigens (HFA) are present in >90% of the human population, according to some reports even in >99% of individuals. Therefore, patients lacking HFA may become challenging for transfusion support because compatible blood is hardly found, and if the patient carries alloantibodies, the cross-match will be positive with virtual every red cell unit tested. METHODS: In this study, we applied high-throughput blood group SNP genotyping on >37,000 Swiss blood donors, intending to identify homozygous carriers of low-frequency blood group antigens (LFA). RESULTS: 326 such individuals were identified and made available to transfusion specialists for future support of patients in need of rare blood products. CONCLUSION: Thorough comparison of minor allele frequencies using population genetics revealed heterogeneity of allele distributions among Swiss blood donors which may be explained by the topographical and cultural peculiarities of Switzerland. Moreover, geographically localized donor subpopulations are described which contain above-average numbers of individuals carrying rare blood group genotypes.

17.
Anal Chem ; 89(3): 1632-1641, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28105805

RESUMO

Femtosecond laser ablation/ionization mass spectrometry (LIMS) has been applied to probe the spatial element composition of three ternary Cu-Sn-Pb model bronze alloys (lead bronzes: CuSn10Pb10, CuSn7Pb15, and CuSn5Pb20), which were recently identified as high-performance cathode materials in the context of electro-organic synthesis (dehalogenation, deoxygenation) of pharmaceutically relevant building blocks. The quantitative and spatially resolved element analysis of such cathode materials will help in understanding the observed profound differences in their electrochemical reactivity and stability. For that purpose, we developed a measurement procedure using the LIMS technique which allows analyzing the element composition of these ternary alloys in all three spatial dimensions. Their chemical composition was determined spotwise, by ablating material from various surface locations on a 4 × 4 raster array (50 µm pitch distance, ablation crater diameter of ∼20 µm). The element analyses show significant chemical inhomogeneities in all three ternary bronze alloys with profound local deviations from their nominal bulk compositions and indicate further differences in the nature and origin of these compositional inhomogeneities. In addition, the element analyses showed specific compositional correlations among the major elements (Cu, Sn, and Pb) in these alloys. On selected sample positions minor (Ni, Zn, Ag, and Sb) and trace elements (C, P, Fe, and As) were quantified. These results are in agreement with inductively coupled plasma collision/reaction interface mass spectrometry (ICP-CRI-MS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) reference measurements, thus proving the LIMS depth profiling technique as a powerful alternative methodology to conventional quantification techniques with the advantage, however, of a highly localized measurement capability.

18.
Transfusion ; 57(5): 1272-1279, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28295360

RESUMO

BACKGROUND: Alloimmunization against human platelet antigens (HPAs) during pregnancy is rare but can lead to severe bleeding disorders, such as fetal and neonatal alloimmune thrombocytopenia. STUDY DESIGN AND METHODS: In a cohort of 241 uncomplicated pregnancies, we investigated the immunogenicity of HPA mismatches and correlated HLA sensitization with HPA antibody formation. HPA antibodies were measured with a Luminex-based multiplex assay. RESULTS: HPA mismatches were observed in 109 of 241 pregnancies (45%), but child-specific HPA antibodies were only found in two of 109 cases (2%), indicating a low immunogenicity. Only nine of 241 women (4%) had detectable HPA antibodies. HLA sensitization was identified as a strong and independent predictor for HPA antibody formation (hazard ratio, 10.2; 95% confidence interval, 1.8-193; p = 0.006), whereas the number of pregnancies was not. CONCLUSION: Our observational data indicated a low immunogenicity of HPA and suggest that a broader immune response-inferred by HLA sensitization-is probably associated with HPA antibody induction.


Assuntos
Antígenos de Plaquetas Humanas/imunologia , Antígenos HLA/imunologia , Adulto , Formação de Anticorpos/imunologia , Estudos de Coortes , Feminino , Histocompatibilidade Materno-Fetal , Humanos , Gravidez , Trombocitopenia Neonatal Aloimune/etiologia
19.
Nat Prod Rep ; 33(12): 1357-1392, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27722705

RESUMO

Covering up to January 2016Cannabis sativa L. is a prolific, but not exclusive, producer of a diverse group of isoprenylated resorcinyl polyketides collectively known as phytocannabinoids. The modular nature of the pathways that merge into the phytocannabinoid chemotype translates in differences in the nature of the resorcinyl side-chain and the degree of oligomerization of the isoprenyl residue, making the definition of phytocannabinoid elusive from a structural standpoint. A biogenetic definition is therefore proposed, splitting the phytocannabinoid chemotype into an alkyl- and a ß-aralklyl version, and discussing the relationships between phytocannabinoids from different sources (higher plants, liverworts, fungi). The startling diversity of cannabis phytocannabinoids might be, at least in part, the result of non-enzymatic transformations induced by heat, light, and atmospheric oxygen on a limited set of major constituents (CBG, CBD, Δ9-THC and CBC and their corresponding acidic versions), whose degradation is detailed to emphasize this possibility. The diversity of metabotropic (cannabinoid receptors), ionotropic (thermos-TRPs), and transcription factors (PPARs) targeted by phytocannabinoids is discussed. The integrated inventory of these compounds and their biological macromolecular end-points highlights the opportunities that phytocannabinoids offer to access desirable drug-like space beyond the one associated to the narcotic target CB1.


Assuntos
Canabinoides , Cannabis/química , Canabinoides/química , Canabinoides/isolamento & purificação , Canabinoides/farmacologia , Estrutura Molecular
20.
Br J Haematol ; 174(4): 624-36, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27072601

RESUMO

Results of genotyping with true high-throughput capability for MNSs antigens are underrepresented, probably because of technical issues, due to the high level of nucleotide sequence homology of the paralogous genes GYPA, GYPB and GYPE. Eight MNSs-specific single nucleotide polymorphisms (SNP) were detected using matrix-assisted laser desorption/ionization, time-of-flight mass spectrometry (MALDI-TOF MS) in 5800 serologically M/N and S/s pre-typed Swiss blood donors and 50 individuals of known or presumptive black African ethnicity. Comparison of serotype with genotype delivered concordance rates of 99·70% and 99·90% and accuracy of genotyping alone of 99·88% and 99·95%, for M/N and S/s, respectively. The area under the curve of peak signals was measured in intron 1 of the two highly homologous genes GYPB and GYPE and allowed for gene copy number variation estimates in all individuals investigated. Elevated GYPB:GYPE ratios accumulated in several carriers of two newly observed GYP*401 variants, termed type G and H, both encoding for the low incidence antigen St(a). In black Africans, reduced GYPB gene contents were proven in pre-typed S-s-U- phenotypes and could be reproduced in unknown specimens. Quantitative gene copy number estimates represented a highly attractive supplement to conventional genotyping, solely based on MNSs SNPs.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Dosagem de Genes , Genótipo , Sistema do Grupo Sanguíneo MNSs/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Alelos , População Negra , Etnicidade , Glicoforinas/genética , Humanos , Polimorfismo de Nucleotídeo Único
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