Nontelomeric TRF2-REST Interaction Modulates Neuronal Gene Silencing and Fate of Tumor and Stem Cells

SummaryRemoval of TRF2, a telomere shelterin protein, recapitulates key aspects of telomere attrition including the DNA-damage response and cell-cycle arrest [1]. Distinct from the response of proliferating cells to loss of TRF2 [2, 3], in rodent noncycling cells, TRF2 inhibition promotes differentiation and growth [4, 5]. However, the mechanism that couples telomere gene-silencing features [6–8] to differentiation programs has yet to be elucidated. Here we describe an extratelomeric function of TRF2 in the regulation of neuronal genes mediated by the interaction of TRF2 with repressor element 1-silencing transcription factor (REST), a master repressor of gene networks devoted to neuronal functions [9–12]. TRF2-REST complexes are readily detected by coimmunoprecipitation assays and are localized to aggregated PML-nuclear bodies in undifferentiated pluripotent human NTera2 stem cells. Inhibition of TRF2, either by a dominant-negative mutant or by RNA interference, dissociates TRF2-REST complexes resulting in ubiquitin-proteasomal degradation of REST. Consequentially, REST-targeted neural genes (L1CAM, β3-tubulin, synaptophysin, and others) are derepressed, resulting in acquisition of neuronal phenotypes. Notably, selective damage to telomeres without affecting TRF2 levels causes neither REST degradation nor cell differentiation. Thus, in addition to protecting telomeres, TRF2 possesses a novel role in stabilization of REST thereby controlling neural tumor and stem cell fate

Nephrostomy-free percutaneous nephrolithotripsy: intraoperative hemostasis methods of the percutaneous tract

Review based on the analysis of more than 40 scientific papers published in the Pubmed and Medline databases from 1984 to 2019, dedicated to intraoperative hemostasis of the percutaneous tract and its tightness during nephrostomyfree percutaneous nephrolithotomy (PCNL). The article aimed to summarize scientific data on this issue. We presented information about the history and development of percutaneous surgery in the treatment of urolithiasis. In our review, we have been demonstrated various methods of surgical and intraoperative hemostasis during nephrostomy-free PCNL

Alterações eletrocardiográficas na intoxicação aguda por antidepressivo tricíclico e suas implicações clínicas

Introduction: The acute poisoning by tricyclic antidepressants is common in emergency rooms. Abnormalities in 12-lead electrocardiogram (ECG) are associated with this type of poisoning, with diagnostic and prognostic implications. The ECG may have incremental value especially in situations of altered consciousness, seizures or heart rhythm disturbances associated. Objective: To review the electrocardiographic changes described in tricyclic antidepressant poisoning and to establish their prognostic implications in the management of this condition. Methods: Bibliographic search in MEDLINE (PubMed) limited to articles published between 1980 and 2010 in English, using key words (tricyclic antidepressant overdose OR tricyclic antidepressant intoxication OR tricyclic antidepressant poisoning OR tricyclic antidepressant ingestion AND electrocardiography). Of the 133 articles identified, 44 were selected for review. Results: We identified prevalent as changes with diagnostic power in descending order the following findings: deviation of 40 ms terminal of QRS to the right of the frontal plane (from 61.0 to 83.0%), sinus tachycardia (40.7 to 57.7 %), QTc prolongation (8.2 to 53.0%), ratio R / S in aVR> 0.7 (28.8 to 32.9%), prolongation of QRS (8.2 to 21.3% ) and Brugada-pattern, the evidence is sparse, but suggestive of a greater chance of seizures and hypotension. Conclusion: The ECG is an instrument easily performed in the emergency room, providing diagnostic and prognostic information for poisoning by tricyclic and should be performed in all patients with suspicion of intoxicationIntrodução: A intoxicação aguda por antidepressivos tricíclicos é comum nas salas de emergência. Anormalidades no eletrocardiograma de 12 derivações (ECG) são associadas a este tipo de intoxicação, com implicações diagnósticas e prognósticas. O ECG pode ter valor incremental principalmente em situações de alteração de consciência, convulsões ou distúrbios do ritmo cardíaco associado. Objetivo: Revisar as principais alterações eletrocardiográficas descritas na intoxicação por antidepressivos tricíclicos e estabelecer suas implicações prognósticas no manejo desta condição clínica. Metodologia: Pesquisa bibliográfica no MEDLINE (PubMEd) limitada aos artigos publicados entre 1980 e 2010 em língua inglesa, utilizando-se unitermos (tricyclic antidepressant overdose OR tricyclic antidepressant intoxication OR tricyclic antidepressant poisoning OR tricyclic antidepressant ingestion AND electrocardiography). Dos 133 artigos identificados, foram selecionados 44 para a revisão.  Resultado: Foram identificados como alterações prevalentes com poder diagnóstico em ordem decrescente os seguintes achados: desvio dos 40 ms terminais do QRS para a direita do plano frontal (61,0-83,0%), taquicardia sinusal (40,7-57,7%), prolongamento do QTc (8,2-53,0%),relação R/S em aVR>0,7 (28,8-32,9%), prolongamento do QRS (8,2-21,3%) e padrão Brugada-like (2,3-15,3%).  Destes achados, somente o prolongamento do QRS foi prognóstico para morte, convulsão e arritmia e o prolongamento do QTc e a relação R/S em aVR>0,7 para arritmia ventricular. Para o padrão Brugada-like , as evidências são escassas, mas sugestivas de maior chance de convulsão e hipotensão. Conclusão: O ECG é um instrumento de fácil realização na sala de urgência, fornecendo informações diagnósticas e prognosticas para a intoxicação por tricíclicos, devendo ser realizado em todo paciente com suspeita desta intoxicação.

Myocardial ultrasonic tissue characterization in patients with thyroid dysfunction

<p>Abstract</p> <p>Background</p> <p>Structural myocardial abnormalities have been extensively documented in hypothyroidism. Experimental studies in animal models have also shown involvement of thyroid hormones in gene expression of myocardial collagen. This study was planned to investigate the ability of ultrasonic tissue characterization, as evaluated by integrated backscatter (IBS), to early identify myocardial involvement in thyroid dysfunction.</p> <p>Patients and Methods</p> <p>We studied 15 patients with hyperthyroidism (HYPER), 8 patients with hypothyroidism (HYPO), 14 patients with subclinical hypothyroidism (SCH) and 19 normal (N) subjects, who had normal LV systolic function. After treatment, 10 HYPER, 6 HYPO, and 8 SCH patients were reevaluated. IBS images were obtained and analyzed in parasternal short axis (papillary muscle level) view, at left ventricular (LV) posterior wall. The following IBS variables were analyzed: 1) the corrected coefficient (CC) of IBS, obtained by dividing IBS intensity by IBS intensity measured in a rubber phantom, using the same equipment adjustments, at the same depth; 2) cardiac cyclic variation (CV) of IBS - peak-to-peak difference between maximal and minimal values of IBS during cardiac cycle; 3) cardiac cyclic variation index (CVI) of IBS - percentual relationship between the cyclic variation (CV) and the mean value of IBS intensity.</p> <p>Results</p> <p>CC of IBS was significantly larger (p < 0.05) in HYPER (1.57 ± 0.6) and HYPO (1.53 ± 0.3) as compared to SCH (1.32 ± 0.3) or N (1.15 ± 0.27). The CV (dB) (HYPO: 7.5 ± 2.4; SCH: 8.2 ± 3.1; HYPER: 8.2 ± 2.0) and the CVI (HYPO: 35.6 ± 19.7%; SCH: 34.7 ± 17.5%; HYPER: 37.8 ± 11.6%) were not significantly different in patients with thyroid dysfunction as compared to N (7.0 ± 2.0 and 44.5 ± 15.1%).</p> <p>Conclusions</p> <p>CC of IBS was able to differentiate cardiac involvement in patients with overt HYPO and HYPER who had normal LV systolic function. These early myocardial structural abnormalities were partially reversed by drug therapy in HYPER group. On the other hand, although mean IBS intensity tended to be slightly larger in patients with SCH as compared to N, this difference was not statistical significant.</p

Defining functional DNA elements in the human genome

With the completion of the human genome sequence, attention turned to identifying and annotating its functional DNA elements. As a complement to genetic and comparative genomics approaches, the Encyclopedia of DNA Elements Project was launched to contribute maps of RNA transcripts, transcriptional regulator binding sites, and chromatin states in many cell types. The resulting genome-wide data reveal sites of biochemical activity with high positional resolution and cell type specificity that facilitate studies of gene regulation and interpretation of noncoding variants associated with human disease. However, the biochemically active regions cover a much larger fraction of the genome than do evolutionarily conserved regions, raising the question of whether nonconserved but biochemically active regions are truly functional. Here, we review the strengths and limitations of biochemical, evolutionary, and genetic approaches for defining functional DNA segments, potential sources for the observed differences in estimated genomic coverage, and the biological implications of these discrepancies. We also analyze the relationship between signal intensity, genomic coverage, and evolutionary conservation. Our results reinforce the principle that each approach provides complementary information and that we need to use combinations of all three to elucidate genome function in human biology and disease

Ethylene receptor ETR2 controls trichome branching by regulating microtubule assembly in Arabidopsis thaliana

The single-celled trichome of Arabidopsis thaliana is a widely used model system for studying cell development. While the pathways that control the later stages of trichome development are well characterized, the early signalling events that co-ordinate these pathways are less well understood. Hormones such as gibberellic acid, salicylic acid, cytokinins, and ethylene are known to affect trichome initiation and development. To understand the role of the plant hormone ethylene in trichome development, an Arabidopsis loss-of-function ethylene receptor mutant, etr2-3, which has completely unbranched trichomes, is analysed in this study. It was hypothesized that ETR2 might affect the assembly of the microtubule cytoskeleton based on analysis of the cytoskeleton in developing trichomes, and exposures to paclitaxol and oryzalin, which respectively act either to stabilize or depolymerize the cytoskeleton. Through epistatic and gene expression analyses it is shown that ETR2 is positioned upstream of CHROMATIN ASSEMBLY FACTOR1 and TRYPTICHON and is independent of the GLABRA2 and GLABRA3 pathways. These results help extend understanding of the early events that control trichome development and identify a signalling pathway through which ethylene affects trichome branching

ChIP-seq guidelines and practices of the ENCODE and modENCODE consortia

Chromatin immunoprecipitation (ChIP) followed by high-throughput DNA sequencing (ChIP-seq) has become a valuable and widely used approach for mapping the genomic location of transcription-factor binding and histone modifications in living cells. Despite its widespread use, there are considerable differences in how these experiments are conducted, how the results are scored and evaluated for quality, and how the data and metadata are archived for public use. These practices affect the quality and utility of any global ChIP experiment. Through our experience in performing ChIP-seq experiments, the ENCODE and modENCODE consortia have developed a set of working standards and guidelines for ChIP experiments that are updated routinely. The current guidelines address antibody validation, experimental replication, sequencing depth, data and metadata reporting, and data quality assessment. We discuss how ChIP quality, assessed in these ways, affects different uses of ChIP-seq data. All data sets used in the analysis have been deposited for public viewing and downloading at the ENCODE (http://encodeproject.org/ENCODE/) and modENCODE (http://www.modencode.org/) portals

Purchasing management in a tertiary teaching hospital: a case study

Modelo do Estudo: Estudo de Caso. Objetivo do Estudo: O presente trabalho visou estudar o processo de compras e programação de materiais de um hospital público de ensino de nível terciário e analisar os perfis de itens de materiais de consumo faltantes em determinado período, com a finalidade de identificar como ferramentas de gestão de materiais podem ajudar na definição de políticas de compras e estoque. Metodologia: O estudo foi elaborado com base em análises qualitativas e quantitativas. As primeiras foram feitas por meio de coleta de dados relativos ao entendimento dos processos e estrutura interna da Divisão de Materiais do Hospital através de observação e entrevistas semiestruturadas entre o período de setembro a novembro de 2013. A relação dos itens faltantes em 2012 e 2013 foi obtida através do sistema de informação da instituição e a partir destes dados foram feitas as análises quantitativas dos perfis destes itens segundo as classificações ABC e VEN (ou XYZ). Resultado: Os resultados apontam que dos 8.595 itens de materiais de consumo do Hospital apenas 5% em quantidade são classificados como A na curva ABC, no entanto tais itens correspondem a 42% em valores. Já os itens vitais representam 49% do valor e 46% em termos de quantidade. Quando analisadas em conjunto, as duas curvas apontam que a maioria das quantidades de materiais de consumo do Hospital são classificados como vitais da curva C (36,35%) e os itens não essenciais da curva A representam tanto em valor como em quantidade a menor parcela de materiais. O perfil dos itens faltantes em 2012 e 2013 são semelhantes, o maior índice de faltas está nos itens vitais da curva C e a menor nos itens não essenciais da curva A. Conclusão: Por meio do estudo foi possível concluir que a definição de políticas de compras e estoques que analisem não somente recursos econômicos, mas também a criticidade dos itens para o funcionamento dos processos é fundamental, principalmente levando em consideração o atual contexto das organizações de saúde públicas, a fim de melhor otimizar recursos e minimizar faltas.Model Study: Case Study. Purpose of the Study: This study aims to explore the purchasing materials process in a tertiary teaching hospital and analyze the missing items profiles in a given period in order to identify how materials management tools can help optimizing purchasing and inventory policies. Methodology: The study was based on qualitative and quantitative analyses. The first was made by means of collecting data to understand both processes and internal structure of the Materials Division through observation and semi-structured interviews between September-November 2013. A list of missing items in 2012 and 2013 was obtained from system information in order to analyze the profiles of these items according to the ABC and VEN (or XYZ) ratings. Results: The results show that out of 8,595 items of consumable materials, only 5 % in volume are classified as A in ABC curve, however such items correspond to 42 % in value. On the other hand, vital items represent 49 % on value and 46 % in terms of quantity. When analyzed together, the two curves show that most quantities of consumables materials are classified as vital from the C curve (36.35%) whereas non-essential items from the A curve represent both in value and in volume the smallest amount portion of materials. The missing items profile in 2012 and 2013 were similar, the highest rate of faults is from vital and C curve materials and the smaller, of nonessentials of the A curve. Conclusion: Through the study, it can be concluded that the definition of procurement policies inventories from the analyses of not only economic resources, but also item’s criticality to processes is essential, especially considering the current context of public health organizations, in order to optimize resources and minimize materials faults

NELF Potentiates Gene Transcription in the Drosophila Embryo

A hallmark of genes that are subject to developmental regulation of transcriptional elongation is association of the negative elongation factor NELF with the paused RNA polymerase complex. Here we use a combination of biochemical and genetic experiments to investigate the in vivo function of NELF in the Drosophila embryo. NELF associates with different gene promoter regions in correlation with the association of RNA polymerase II (Pol II) and the initial activation of gene expression during the early stages of embryogenesis. Genetic experiments reveal that maternally provided NELF is required for the activation, rather than the repression of reporter genes that emulate the expression of key developmental control genes. Furthermore, the relative requirement for NELF is dictated by attributes of the flanking cis-regulatory information. We propose that NELF-associated paused Pol II complexes provide a platform for high fidelity integration of the combinatorial spatial and temporal information that is central to the regulation of gene expression during animal development