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Conserved and divergent DNA recognition specificities and functions of R2 retrotransposon N-terminal domains.
R2 non-long terminal repeat (non-LTR) retrotransposons are among the most extensively distributed mobile genetic elements in multicellular eukaryotes and show promise for applications in transgene supplementation of the human genome. They insert new gene copies into a conserved site in 28S ribosomal DNA with exquisite specificity. R2 clades are defined by the number of zinc fingers (ZFs) at the N terminus of the retrotransposon-encoded protein, postulated to additively confer DNA site specificity. Here, we illuminate general principles of DNA recognition by R2 N-terminal domains across and between clades, with extensive, specific recognition requiring only one or two compact domains. DNA-binding and protection assays demonstrate broadly shared as well as clade-specific DNA interactions. Gene insertion assays in cells identify the N-terminal domains sufficient for target-site insertion and reveal roles in second-strand cleavage or synthesis for clade-specific ZFs. Our results have implications for understanding evolutionary diversification of non-LTR retrotransposon insertion mechanisms and the design of retrotransposon-based gene therapies
On the Refinement of Write-Ahead Logging
Many hackers worldwide would agree that, had it not been for Smalltalk, the synthesis of voice-over-IP might never have occurred. After years of unfortunate research into mas- sive multiplayer online role-playing games, we verify the understanding of XML. we prove not only that the UNIVAC computer and journaling file systems are always incompati- ble, but that the same is true for virtual ma- chines
Prehospital neurological deterioration in stroke
BACKGROUND AND PURPOSE:
Patients with stroke can experience neurological deterioration in the prehospital setting. We evaluated patients with stroke to determine factors associated with prehospital neurological deterioration (PND).
METHODS:
Among the Greater Cincinnati/Northern Kentucky region (population ~1.3 million), we screened all 15 local hospitals' admissions from 2010 for acute stroke and included patients aged ≥20. The GCS was compared between emergency medical services (EMS) arrival and hospital arrival, with decrease ≥2 points considered PND. Data obtained retrospectively included demographics, medical history and medication use, stroke subtype (eg, ischaemic stroke (IS), intracerebral haemorrhage (ICH), subarachnoid haemorrhage (SAH)) and IS subtype (eg, small vessel, large vessel, cardioembolic), seizure at onset, time intervals between symptom onset, EMS arrival and hospital arrival, EMS level of training, and blood pressure and serum glucose on EMS arrival.
RESULTS:
Of 2708 total patients who had a stroke, 1092 patients (median (IQR) age 74 (61-83) years; 56% women; 21% black) were analysed. PND occurred in 129 cases (12%), including 9% of IS, 24% of ICH and 16% of SAH. In multivariable analysis, black race, atrial fibrillation, haemorrhagic subtype and ALS level of transport were associated with PND.
CONCLUSION:
Haemorrhage and atrial fibrillation is associated with PND in stroke, and further investigation is needed to establish whether PND can be predicted. Further studies are also needed to assess whether preferential transport of patients with deterioration to hospitals equipped with higher levels of care is beneficial, identify why race is associated with deterioration and to test therapies targeting PND
Desenvolvimento e Validação da Escala de Literacia Mediática e Informacional para Alunos dos 2º e 3º Ciclos do Ensino Básico em Portugal
A comunicação e a partilha de significados num mundo altamente mediatizado requer múltiplas literacias. Independentemente das definições
e abordagens, estas literacias têm vindo a abrir debates crÃticos sobre quais as competências que os cidadãos devem ter e desde quando elas
devem ser adquiridas. No presente estudo damos conta do processo de desenvolvimento e validação de uma Escala de Literacia Mediática e
Informacional (ELMI) para alunos dos 2º e 3º ciclos do Ensino Básico em Portugal. A validade de construto foi examinada via Análise Fatorial Exploratória (AFE) para uma amostra de 1151 participantes. A AFE revelou
uma estrutura trifatorial constituÃda por 22 itens que explicam 53.23% da variância total. A escala apresenta uma consistência interna global
excelente (ωt = .92), com adequada consistência interna para todas as subescalas (α de Cronbach e α Ordinal > .70). Os resultados evidenciam
boas qualidades psicométricas da ELMI que poderá ser um instrumentovantajoso para o prognóstico e avaliação de intervenções relacionadas
com a literacia mediática.
Palavras-Chave: literacia mediática e informacional; validação de escala; educação para os media;
2º e 3º ciclos do ensino básico
Human senescent fibroblasts trigger progressive lung fibrosis in mice
Cell senescence has recently emerged as a potentially relevant pathogenic mechanism in fibrosing interstitial lung diseases (f-ILDs), particularly in idiopathic pulmonary fibrosis. We hypothesized that senescent human fibroblasts may suffice to trigger a progressive fibrogenic reaction in the lung. To address this, senescent human lung fibroblasts, or their secretome (SASP), were instilled into the lungs of immunodeficient mice. We found that: (1) human senescent fibroblasts engraft in the lungs of immunodeficient mice and trigger progressive lung fibrosis associated to increasing levels of mouse senescent cells, whereas non-senescent fibroblasts do not trigger fibrosis; (2) the SASP of human senescent fibroblasts is pro-senescence and pro-fibrotic both in vitro when added to mouse recipient cells and in vivo when delivered into the lungs of mice, whereas the conditioned medium (CM) from non-senescent fibroblasts lacks these activities; and, (3) navitoclax, nintedanib and pirfenidone ameliorate lung fibrosis induced by senescent human fibroblasts in mice, albeit only navitoclax displayed senolytic activity. We conclude that human senescent fibroblasts, through their bioactive secretome, trigger a progressive fibrogenic reaction in the lungs of immunodeficient mice that includes the induction of paracrine senescence in the cells of the host, supporting the concept that senescent cells actively contribute to disease progression in patients with f-ILDs
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