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1.
J Holist Nurs ; 40(3): 219-226, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34636677

RESUMO

The purpose of this study was to examine nurse coach scope of practice in relation to existing evidence-based guideline interventions using the Omaha System. The majority of interventions were within scope for nurse coach practice, and problem, category, and target terms showed differential nurse coach practice applicability across interventions. The Omaha System terminology was aligned with nurse coach practice in that both represent and employ comprehensive and holistic perspectives. This study provides a platform for multiple initiatives in nurse coach quality and documentation and provides a methodology for examining the Omaha System guidelines and interventions for other interprofessional roles.


Assuntos
Cuidados de Enfermagem , Âmbito da Prática , Documentação/métodos , Medicina Baseada em Evidências , Humanos , Vocabulário Controlado
2.
Nature ; 537(7621): 535-538, 2016 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-27580034

RESUMO

Biological activity is a major factor in Earth's chemical cycles, including facilitating CO2 sequestration and providing climate feedbacks. Thus a key question in Earth's evolution is when did life arise and impact hydrosphere-atmosphere-lithosphere chemical cycles? Until now, evidence for the oldest life on Earth focused on debated stable isotopic signatures of 3,800-3,700 million year (Myr)-old metamorphosed sedimentary rocks and minerals from the Isua supracrustal belt (ISB), southwest Greenland. Here we report evidence for ancient life from a newly exposed outcrop of 3,700-Myr-old metacarbonate rocks in the ISB that contain 1-4-cm-high stromatolites-macroscopically layered structures produced by microbial communities. The ISB stromatolites grew in a shallow marine environment, as indicated by seawater-like rare-earth element plus yttrium trace element signatures of the metacarbonates, and by interlayered detrital sedimentary rocks with cross-lamination and storm-wave generated breccias. The ISB stromatolites predate by 220 Myr the previous most convincing and generally accepted multidisciplinary evidence for oldest life remains in the 3,480-Myr-old Dresser Formation of the Pilbara Craton, Australia. The presence of the ISB stromatolites demonstrates the establishment of shallow marine carbonate production with biotic CO2 sequestration by 3,700 million years ago (Ma), near the start of Earth's sedimentary record. A sophistication of life by 3,700 Ma is in accord with genetic molecular clock studies placing life's origin in the Hadean eon (>4,000 Ma).


Assuntos
Fósseis , Sedimentos Geológicos/microbiologia , Origem da Vida , Água do Mar/microbiologia , Organismos Aquáticos , Austrália , Vida , Fatores de Tempo
3.
Nat Commun ; 7: 10665, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26879892

RESUMO

The extension of subduction processes into the Eoarchaean era (4.0-3.6 Ga) is controversial. The oldest reported terrestrial olivine, from two dunite lenses within the ∼3,720 Ma Isua supracrustal belt in Greenland, record a shape-preferred orientation of olivine crystals defining a weak foliation and a well-defined lattice-preferred orientation (LPO). [001] parallel to the maximum finite elongation direction and (010) perpendicular to the foliation plane define a B-type LPO. In the modern Earth such fabrics are associated with deformation of mantle rocks in the hanging wall of subduction systems; an interpretation supported by experiments. Here we show that the presence of B-type fabrics in the studied Isua dunites is consistent with a mantle origin and a supra-subduction mantle wedge setting, the latter supported by compositional data from nearby mafic rocks. Our results provide independent microstructural data consistent with the operation of Eoarchaean subduction and indicate that microstructural analyses of ancient ultramafic rocks provide a valuable record of Archaean geodynamics.

4.
Science ; 335(6072): 1051-2, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22383835
5.
Appl Environ Microbiol ; 74(8): 2480-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18310417

RESUMO

Between March and May 2006, a Texas hospital identified five Mycobacterium mucogenicum bloodstream infections among hospitalized oncology patients using fluorescence high-performance liquid chromatography analysis of mycolic acids. Isolates from blood cultures were compared to 16 isolates from environmental sites or water associated with this ward. These isolates were further characterized by hsp65, 16S rRNA, and rpoB gene sequencing, hsp65 PCR restriction analysis, and molecular typing methods, including repetitive element PCR, random amplified polymorphic DNA PCR, and pulsed-field gel electrophoresis (PFGE) of large restriction fragments. Three of five patient isolates were confirmed as M. mucogenicum and were in a single cluster as determined by all identification and typing methods. The remaining two patient isolates were identified as different strains of Mycobacterium phocaicum by rpoB sequence analysis. One of these matched an environmental isolate from a swab of a hand shower in the patient's room, while none of the clinical isolates of M. mucogenicum matched environmental strains. Among the other 15 environmental isolates, 11 were identified as M. mucogenicum and 4 as M. phocaicum strains, all of which were unrelated by typing methods. Although the 16S rRNA gene sequences matched for all 14 M. mucogenicum isolates, there were two each of the hsp65 and rpoB sequevars, seven PCR typing patterns, and 12 PFGE patterns. Among the seven M. phocaicum isolates were three 16S rRNA sequevars, two hsp65 sequevars, two rpoB sequevars, six PCR typing patterns, and six PFGE patterns. This outbreak represents the first case of catheter-associated bacteremia caused by M. phocaicum and the first report of clinical isolates from a U.S. hospital. The investigation highlights important differences in the available typing methods for mycobacteria and demonstrates the genetic diversity of these organisms even within narrow confines of time and space.


Assuntos
Bacteriemia/microbiologia , Infecção Hospitalar/microbiologia , Surtos de Doenças , Microbiologia Ambiental , Variação Genética , Infecções por Mycobacterium/microbiologia , Mycobacterium/classificação , Idoso , Bacteriemia/epidemiologia , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Chaperonina 60 , Chaperoninas/genética , Análise por Conglomerados , Infecção Hospitalar/epidemiologia , Impressões Digitais de DNA , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , RNA Polimerases Dirigidas por DNA/genética , Eletroforese em Gel de Campo Pulsado , Feminino , Genótipo , Hospitais , Humanos , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Mycobacterium/genética , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium/epidemiologia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Análise de Sequência de DNA , Texas/epidemiologia
6.
Science ; 318(5858): 1907-10, 2007 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-18096803

RESUMO

The oldest rocks-3.85 billion years old-from southwest Greenland have coupled neodymium-142 excesses (from decay of now-extinct samarium-146; half-life, 103 million years) and neodymium-143 excesses (from decay of samarium-147; half-life, 106 billion years), relative to chondritic meteorites, that directly date the formation of chemically distinct silicate reservoirs in the first 30 million to 75 million years of Earth history. The differences in 142Nd signatures of coeval rocks from the two most extensive crustal relicts more than 3.6 billion years old, in Western Australia and southwest Greenland, reveal early-formed large-scale chemical heterogeneities in Earth's mantle that persisted for at least the first billion years of Earth history. Temporal variations in 142Nd signatures track the subsequent incomplete remixing of very-early-formed mantle chemical domains.

7.
Differentiation ; 71(4-5): 251-61, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12823226

RESUMO

Fibronectin (FN), a large dimeric glycoprotein, functions primarily as a connecting molecule in the extracellular matrices of tissues by mediating both cell-matrix and matrix-matrix interactions. All members of the FN family are products of a single FN gene; heterogeneity arises from the alternative splicing of at least three regions (IIIB, IIIA, and V) during processing of a common primary transcript. During chick embryonic limb chondrogenesis, FN structure changes from B+A+ in precartilage mesenchyme to B+A- in differentiated cartilage, and exon IIIA has been shown to be necessary for the process of mesenchymal cellular condensation, a requisite event that precedes overt expression of chondrocyte phenotype. This study aims to investigate the mechanistic action of the FN isoforms in mesenchymal chondrogenesis and, in particular, to identify the specific cellular function in mesenchymal condensation mediated by the mesenchymal (B+A+) FN isoform. Full-length cDNAs corresponding to four splice variants (B+A+, B+A-, B-A+, B-A-) of FN were constructed, and expressed the corresponding proteins using a baculovirus expression vector system. Cell adhesion assays with purified proteins showed that, although the relative levels of cell attachment were approximately the same, chick limb-bud mesenchymal cells spread up to 40 % less on mesenchymal (B+A+) FN than on cartilage (B+A-) FN, (B-A+) FN, or plasma (B-A-) FN. Cellular condensation and chondrogenic differentiation were also promoted in high-density micromass cultures of limb mesenchymal cells plated onto B+A+ FN. These observations suggest that the process of mesenchymal condensation is mediated at least in part by the enhanced ability of chondrogenic mesenchymal cells to migrate and aggregate as a consequence of residing in and interacting with mesenchymal FN. Our findings are consistent with and provide a mechanistic basis for previous observations that rounding of limb mesenchymal cells precedes the onset of chondrogenesis.


Assuntos
Condrogênese/fisiologia , Extremidades/embriologia , Fibronectinas/genética , Mesoderma/metabolismo , Animais , Baculoviridae , Embrião de Galinha , Fibronectinas/metabolismo , Vetores Genéticos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estrutura Terciária de Proteína , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Análise de Sequência de Proteína
8.
Nature ; 422(6929): 294-7, 2003 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-12646918

RESUMO

Variations in the 187Os/188Os isotopic signature of mantle and mantle-derived rocks have been thought to provide a powerful chemical tracer of deep Earth structure. Many studies have inferred from such data that a long-lived, high-rhenium component exists in the deep mantle (187Re is the parent isotope decaying to 187Os, with a half-life of approximately 42 billion years), and that this reservoir probably consists of subducted oceanic crust. The interpretation of these isotopic signatures is, however, dependent on accurate estimates of rhenium and osmium concentrations in all of the main geochemical reservoirs, and the crust has generally been considered to be a minor contributor to such global budgets. In contrast, we here present observations of high rhenium concentrations and low Yb/Re ratios in arc-type melt inclusions. These results indicate strong enrichment of rhenium in undegassed arc rocks, and consequently the continental crust, which results in a crustal estimate of 2 p.p.b. rhenium, as compared to previous estimates of 0.4-0.2 p.p.b. (refs 4, 5). Previous determinations of rhenium in arc materials, which were largely measured on subaerially erupted samples, are likely to be in error owing to rhenium loss during degassing. High mantle-to-crust rhenium fluxes, as observed here, require a revaluation of geochemical models based on the 187Re-187Os decay system.

9.
J Cell Biochem ; 86(1): 45-55, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12112015

RESUMO

The alternative exon EIIIA of the fibronectin gene is included in mRNAs produced in undifferentiated mesenchymal cells but excluded from differentiated chondrocytes. As members of the SR protein family of splicing factors have been demonstrated to be involved in the alternative splicing of other mRNAs, the role of SR proteins in chondrogenesis-associated EIIIA splicing was investigated. SR proteins interacted with chick exon EIIIA sequences that are required for exon inclusion in a gel mobility shift assay. Addition of SR proteins to in vitro splicing reactions increased the rate and extent of exon EIIIA inclusion. Co-transfection studies employing cDNAs encoding individual SR proteins revealed that SRp20 decreased mRNA accumulation in HeLa cells, which make A+ mRNA, apparently by interfering with pre-mRNA splicing. Co-transfection studies also demonstrated that SRp40 increased exon EIIIA inclusion in chondrocytes, but not in HeLa cells, suggesting the importance of cellular context for SR protein activity. Immunoblot analysis did not reveal a relative depletion of SRp40 in chondrocytic cells. Possible mechanisms for regulation of EIIIA splicing in particular, and chondrogenesis associated splicing in general, are discussed.


Assuntos
Processamento Alternativo/genética , Condrogênese/genética , Éxons/genética , Fibronectinas/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Animais , Células Cultivadas , Galinhas , Condrócitos/química , Células HeLa , Humanos , Mesoderma/citologia , Mesoderma/metabolismo , Ligação Proteica , Proteínas de Ligação a RNA/metabolismo , Sequências Reguladoras de Ácido Ribonucleico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Processamento de Serina-Arginina , Transfecção
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