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BACKGROUND: Heart failure (HF) with preserved or mildly reduced ejection fraction includes a heterogenous group of patients. Reclassification into distinct phenogroups to enable targeted interventions is a priority. This study aimed to identify distinct phenogroups, and compare phenogroup characteristics and outcomes, from electronic health record data. METHODS: 2,187 patients admitted to five UK hospitals with a diagnosis of HF and a left ventricular ejection fraction ≥ 40% were identified from the NIHR Health Informatics Collaborative database. Partition-based, model-based, and density-based machine learning clustering techniques were applied. Cox Proportional Hazards and Fine-Gray competing risks models were used to compare outcomes (all-cause mortality and hospitalisation for HF) across phenogroups. RESULTS: Three phenogroups were identified: (1) Younger, predominantly female patients with high prevalence of cardiometabolic and coronary disease; (2) More frail patients, with higher rates of lung disease and atrial fibrillation; (3) Patients characterised by systemic inflammation and high rates of diabetes and renal dysfunction. Survival profiles were distinct, with an increasing risk of all-cause mortality from phenogroups 1 to 3 (p < 0.001). Phenogroup membership significantly improved survival prediction compared to conventional factors. Phenogroups were not predictive of hospitalisation for HF. CONCLUSIONS: Applying unsupervised machine learning to routinely collected electronic health record data identified phenogroups with distinct clinical characteristics and unique survival profiles.
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Registros Electrónicos de Salud , Insuficiencia Cardíaca , Volumen Sistólico , Función Ventricular Izquierda , Humanos , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/mortalidad , Femenino , Masculino , Anciano , Persona de Mediana Edad , Medición de Riesgo , Reino Unido/epidemiología , Factores de Riesgo , Pronóstico , Anciano de 80 o más Años , Bases de Datos Factuales , Aprendizaje Automático no Supervisado , Hospitalización , Factores de Tiempo , Comorbilidad , Causas de Muerte , Fenotipo , Minería de DatosRESUMEN
Mitochondrial mRNAs encode key subunits of the oxidative phosphorylation complexes that produce energy for the cell. In Saccharomyces cerevisiae, mitochondrial translation is under the control of translational activators, specific to each mRNA. In Schizosaccharomyces pombe, which more closely resembles the human system by its mitochondrial DNA structure and physiology, most translational activators appear to be either lacking, or recruited for post-translational functions. By combining bioinformatics, genetic and biochemical approaches we identified two interacting factors, Cbp7 and Cbp8, controlling Cytb production in S. pombe. We show that their absence affects cytb mRNA stability and impairs the detection of the Cytb protein. We further identified two classes of Cbp7/Cbp8 partners and showed that they modulated Cytb or Cox1 synthesis. First, two isoforms of bS1m, a protein of the small mitoribosomal subunit, that appear mutually exclusive and confer translational specificity. Second, a complex of four proteins dedicated to Cox1 synthesis, which includes an RNA helicase that interacts with the mitochondrial ribosome. Our results suggest that S. pombe contains, in addition to complexes of translational activators, a heterogeneous population of mitochondrial ribosomes that could specifically modulate translation depending on the mRNA translated, in order to optimally balance the production of different respiratory complex subunits.
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Proteínas del Complejo de Cadena de Transporte de Electrón/genética , Mitocondrias/genética , Biosíntesis de Proteínas , ARN Mensajero/genética , ARN Mitocondrial/genética , Saccharomyces cerevisiae/genética , Schizosaccharomyces/genética , Biología Computacional/métodos , Citocromos b/genética , Citocromos b/metabolismo , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Proteínas del Complejo de Cadena de Transporte de Electrón/metabolismo , Complejo IV de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/metabolismo , Regulación Fúngica de la Expresión Génica , Mitocondrias/metabolismo , Fosforilación Oxidativa , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estabilidad del ARN , ARN Mensajero/metabolismo , ARN Mitocondrial/metabolismo , Ribosomas/genética , Ribosomas/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/metabolismo , Transactivadores/genética , Transactivadores/metabolismoRESUMEN
BACKGROUND: Systemic adjuvant treatment might mitigate the high risk of disease recurrence in patients with resected stage IIC-III melanoma. The BRIM8 study evaluated adjuvant vemurafenib monotherapy in patients with resected, BRAFV600 mutation-positive melanoma. METHODS: BRIM8 was a phase 3, international, double-blind, randomised, placebo-controlled study that enrolled 498 adults (aged ≥18 years) with histologically confirmed stage IIC-IIIA-IIIB (cohort 1) or stage IIIC (cohort 2) BRAFV600 mutation-positive melanoma that was fully resected. Patients were randomly assigned (1:1) by an interactive voice or web response system to receive twice-daily adjuvant oral vemurafenib 960 mg tablets or matching placebo for 52 weeks (13â×â28-day cycles). Randomisation was done by permuted blocks (block size 6) and was stratified by pathological stage and region in cohort 1 and by region in cohort 2. The investigators, patients, and sponsor were masked to treatment assignment. The primary endpoint was disease-free survival in the intention-to-treat population, evaluated separately in each cohort. Hierarchical analysis of cohort 2 before cohort 1 was prespecified. This trial is registered with ClinicalTrials.gov, number NCT01667419. FINDINGS: The study enrolled 184 patients in cohort 2 (93 were assigned to vemurafenib and 91 to placebo) and 314 patients in cohort 1 (157 were assigned to vemurafenib and 157 to placebo). At the time of data cutoff (April 17, 2017), median study follow-up was 33·5 months (IQR 25·9-41·6) in cohort 2 and 30·8 months (25·5-40·7) in cohort 1. In cohort 2 (patients with stage IIIC disease), median disease-free survival was 23·1 months (95% CI 18·6-26·5) in the vemurafenib group versus 15·4 months (11·1-35·9) in the placebo group (hazard ratio [HR] 0·80, 95% CI 0·54-1·18; log-rank p=0·26). In cohort 1 (patients with stage IIC-IIIA-IIIB disease) median disease-free survival was not reached (95% CI not estimable) in the vemurafenib group versus 36·9 months (21·4-not estimable) in the placebo group (HR 0·54 [95% CI 0·37-0·78]; log-rank p=0·0010); however, the result was not significant because of the prespecified hierarchical prerequisite for the primary disease-free survival analysis of cohort 2 to show a significant disease-free survival benefit. Grade 3-4 adverse events occurred in 141 (57%) of 247 patients in the vemurafenib group and 37 (15%) of 247 patients in the placebo group. The most common grade 3-4 adverse events in the vemurafenib group were keratoacanthoma (24 [10%] of 247 patients), arthralgia (17 [7%]), squamous cell carcinoma (17 [7%]), rash (14 [6%]), and elevated alanine aminotransferase (14 [6%]), although all keratoacanthoma events and most squamous cell carcinoma events were by default graded as grade 3. In the placebo group, grade 3-4 adverse events did not exceed 2% for any of the reported terms. Serious adverse events were reported in 40 (16%) of 247 patients in the vemurafenib group and 25 (10%) of 247 patients in the placebo group. The most common serious adverse event was basal cell carcinoma, which was reported in eight (3%) patients in each group. One patient in the vemurafenib group of cohort 2 died 2 months after admission to hospital for grade 3 hypertension; however, this death was not considered to be related to the study drug. INTERPRETATION: The primary endpoint of disease-free survival was not met in cohort 2, and therefore the analysis of cohort 1 showing a numerical benefit in disease-free survival with vemurafenib versus placebo in patients with resected stage IIC-IIIA-IIIB BRAFV600 mutation-positive melanoma must be considered exploratory only. 1 year of adjuvant vemurafenib was well tolerated, but might not be an optimal treatment regimen in this patient population. FUNDING: F Hoffman-La Roche Ltd.
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Antineoplásicos/uso terapéutico , Carcinoma de Células Escamosas/inducido químicamente , Queratoacantoma/inducido químicamente , Melanoma/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Vemurafenib/uso terapéutico , Adulto , Alanina Transaminasa/sangre , Antineoplásicos/efectos adversos , Artralgia/inducido químicamente , Quimioterapia Adyuvante/efectos adversos , Supervivencia sin Enfermedad , Método Doble Ciego , Erupciones por Medicamentos/etiología , Femenino , Humanos , Metástasis Linfática , Masculino , Melanoma/genética , Melanoma/patología , Melanoma/cirugía , Persona de Mediana Edad , Estadificación de Neoplasias , Proteínas Proto-Oncogénicas B-raf/genética , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/secundario , Neoplasias Cutáneas/cirugía , Vemurafenib/efectos adversosRESUMEN
Mitochondria have their own translation machinery that produces key subunits of the OXPHOS complexes. This machinery relies on the coordinated action of nuclear-encoded factors of bacterial origin that are well conserved between humans and yeast. In humans, mutations in these factors can cause diseases; in yeast, mutations abolishing mitochondrial translation destabilize the mitochondrial DNA. We show that when the mitochondrial genome contains no introns, the loss of the yeast factors Mif3 and Rrf1 involved in ribosome recycling neither blocks translation nor destabilizes mitochondrial DNA. Rather, the absence of these factors increases the synthesis of the mitochondrially-encoded subunits Cox1, Cytb and Atp9, while strongly impairing the assembly of OXPHOS complexes IV and V. We further show that in the absence of Rrf1, the COX1 specific translation activator Mss51 accumulates in low molecular weight forms, thought to be the source of the translationally-active form, explaining the increased synthesis of Cox1. We propose that Rrf1 takes part in the coordination between translation and OXPHOS assembly in yeast mitochondria. These interactions between general and specific translation factors might reveal an evolutionary adaptation of the bacterial translation machinery to the set of integral membrane proteins that are translated within mitochondria.
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ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Regulación Fúngica de la Expresión Génica , Mitocondrias/genética , Proteínas Mitocondriales/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Citocromos b/genética , Citocromos b/metabolismo , ADN Mitocondrial/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Genoma Mitocondrial , Mitocondrias/metabolismo , Proteínas Mitocondriales/química , Proteínas Mitocondriales/metabolismo , ATPasas de Translocación de Protón Mitocondriales/genética , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Modelos Moleculares , Fosforilación Oxidativa , Biosíntesis de Proteínas , Ribosomas/genética , Ribosomas/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
PURPOSE: Patients with glioblastoma who are older or have poor performance status (PS) experience particularly poor clinical outcomes. At the time of study initiation, these patients were treated with short-course radiation therapy (40 Gy in 15 fractions). Olaparib is an oral inhibitor of the DNA repair enzyme poly (ADP-ribose) polymerase (PARP) that is well tolerated as a single agent but exacerbates acute radiation toxicity in extracranial sites. Preclinical data predicted that PARP inhibitors would enhance radiosensitivity in glioblastoma without exacerbating adverse effects on the normal brain. METHODS AND MATERIALS: Phase 1 of the PARADIGM trial was a 3+3 dose-escalation study testing olaparib in combination with radiation therapy (40 Gy 15 fractions) in patients with newly diagnosed glioblastoma who were unsuitable for radical treatment either because they were aged 70 years or older (World Health Organization PS 0-1) or aged 18 to 69 years with PS 2. The primary outcome was the recommended phase 2 dose of olaparib. Secondary endpoints included safety and tolerability, overall survival, and progression-free survival. Effects on cognitive function were assessed via the Mini Mental State Examination. RESULTS: Of 16 eligible patients (56.25% male; median age, 71.5 years [range, 44-78]; 75% PS 0-1), 1 dose-limiting toxicity was reported (grade 3 agitation). Maximum tolerated dose was not reached and the recommended phase 2 dose was determined as 200 mg twice daily. Median overall survival and progression-free survival were 10.8 months (80% CI, 7.3-11.4) and 5.5 months (80% CI, 3.9-5.9), respectively. Mini Mental State Examination plots indicated that cognitive function was not adversely affected by the olaparib-radiation therapy combination. CONCLUSIONS: Olaparib can be safely combined with hypofractionated brain radiation therapy and is well tolerated in patients unsuitable for radical chemoradiation. These results enabled initiation of a randomized phase 2 study and support future trials of PARP inhibitors in combination with radiation therapy for patients with brain tumors.
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Neoplasias Encefálicas , Glioblastoma , Piperazinas , Humanos , Masculino , Anciano , Femenino , Glioblastoma/tratamiento farmacológico , Glioblastoma/radioterapia , Inhibidores de Poli(ADP-Ribosa) Polimerasas/efectos adversos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/radioterapia , Ftalazinas/efectos adversosRESUMEN
Objective: The COVID-19 pandemic was associated with a reduction in the incidence of myocardial infarction (MI) diagnosis, in part because patients were less likely to present to hospital. Whether changes in clinical decision making with respect to the investigation and management of patients with suspected MI also contributed to this phenomenon is unknown. Methods: Multicentre retrospective cohort study in three UK centres contributing data to the National Institute for Health Research Health Informatics Collaborative. Patients presenting to the Emergency Department (ED) of these centres between 1st January 2020 and 1st September 2020 were included. Three time epochs within this period were defined based on the course of the first wave of the COVID-19 pandemic: pre-pandemic (epoch 1), lockdown (epoch 2), post-lockdown (epoch 3). Results: During the study period, 10,670 unique patients attended the ED with chest pain or dyspnoea, of whom 6,928 were admitted. Despite fewer total ED attendances in epoch 2, patient presentations with dyspnoea were increased (p < 0.001), with greater likelihood of troponin testing in both chest pain (p = 0.001) and dyspnoea (p < 0.001). There was a dramatic reduction in elective and emergency cardiac procedures (both p < 0.001), and greater overall mortality of patients (p < 0.001), compared to the pre-pandemic period. Positive COVID-19 and/or troponin test results were associated with increased mortality (p < 0.001), though the temporal risk profile differed. Conclusions: The first wave of the COVID-19 pandemic was associated with significant changes not just in presentation, but also the investigation, management, and outcomes of patients presenting with suspected myocardial injury or MI.
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PPR proteins are a family of ubiquitous RNA-binding factors, found in all the Eukaryotic lineages, and are particularly numerous in higher plants. According to recent bioinformatic analyses, yeast genomes encode from 10 (in S. pombe) to 15 (in S. cerevisiae) PPR proteins. All of these proteins are mitochondrial and very often interact with the mitochondrial membrane. Apart from the general factors, RNA polymerase and RNase P, most yeast PPR proteins are involved in the stability and/or translation of mitochondrially encoded RNAs. At present, some information concerning the target RNA(s) of most of these proteins is available, the next challenge will be to refine our understanding of the function of the proteins and to resolve the yeast PPR-RNA-binding code, which might differ significantly from the plant PPR code.
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Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Mitocondrias/genética , Proteínas de Unión al ARN/metabolismo , Simulación por Computador , ADN Mitocondrial/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Biosíntesis de Proteínas , Estabilidad del ARN , Proteínas de Unión al ARN/genética , Ribonucleasa P/genética , Ribonucleasa P/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/genéticaRESUMEN
Pentatricopeptide repeat (PPR) proteins are particularly numerous in plant mitochondria and chloroplasts, where they are involved in different steps of RNA metabolism, probably due to the repeated 35 amino acid PPR motifs that are thought to mediate interactions with RNA. In non-photosynthetic eukaryotes only a handful of PPR proteins exist, for example the human LRPPRC, which is involved in a mitochondrial disease. We have conducted a systematic study of the PPR proteins in the fission yeast Schizosaccharomyces pombe and identified, in addition to the mitochondrial RNA polymerase, eight proteins all of which localized to the mitochondria, and showed some association with the membrane. The absence of all but one of these PPR proteins leads to a respiratory deficiency and modified patterns of steady state mt-mRNAs or newly synthesized mitochondrial proteins. Some cause a general defect, whereas others affect specific mitochondrial RNAs, either coding or non-coding: cox1, cox2, cox3, 15S rRNA, atp9 or atp6, sometimes leading to secondary defects. Interestingly, the two possible homologs of LRPPRC, ppr4 and ppr5, play opposite roles in the expression of the cox1 mt-mRNA, ppr4 being the first mRNA-specific translational activator identified in S. pombe, whereas ppr5 appears to be a general negative regulator of mitochondrial translation.
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Regulación Fúngica de la Expresión Génica , Genes Mitocondriales , Mitocondrias/genética , Proteínas Mitocondriales/fisiología , Proteínas de Schizosaccharomyces pombe/fisiología , Secuencias de Aminoácidos , Genoma Fúngico , Mitocondrias/metabolismo , Proteínas Mitocondriales/química , Proteínas Mitocondriales/genética , Mutación , Fenotipo , Biosíntesis de Proteínas , ARN/metabolismo , Estabilidad del ARN , ARN Mitocondrial , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/química , Proteínas de Schizosaccharomyces pombe/genética , Homología de Secuencia de AminoácidoRESUMEN
Glioma is one of the most common malignant primary brain tumours in adults, of which, glioblastoma is the most prevalent and malignant entity. Glioma is often diagnosed at a later stage of disease progression, which means it is associated with significant mortality and morbidity. Therefore, there is a need for earlier diagnosis of these tumours, which would require sensitive and specific biomarkers. These biomarkers could better predict glioma onset to improve diagnosis and therapeutic options for patients. While liquid biopsies could provide a cheap and non-invasive test to improve the earlier detection of glioma, there is little known on pre-diagnostic biomarkers which predate disease detection. In this review, we examine the evidence in the literature for pre-diagnostic biomarkers in glioma, including metabolomics and proteomics. We also consider the limitations of these approaches and future research directions of pre-diagnostic biomarkers for glioma.
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Background: No single biomarker currently risk stratifies chronic obstructive pulmonary disease (COPD) patients at the time of an exacerbation, though previous studies have suggested that patients with elevated troponin at exacerbation have worse outcomes. This study evaluated the relationship between peak cardiac troponin and subsequent major adverse cardiac events (MACE) including all-cause mortality and COPD hospital readmission, among patients admitted with COPD exacerbation. Methods: Data from five cross-regional hospitals in England were analysed using the National Institute of Health Research Health Informatics Collaborative (NIHR-HIC) acute coronary syndrome database (2008-2017). People hospitalised with a COPD exacerbation were included, and peak troponin levels were standardised relative to the 99th percentile (upper limit of normal). We used Cox Proportional Hazard models adjusting for age, sex, laboratory results and clinical risk factors, and implemented logarithmic transformation (base-10 logarithm). The primary outcome was risk of MACE within 90 days from peak troponin measurement. Secondary outcome was risk of COPD readmission within 90 days from peak troponin measurement. Results: There were 2487 patients included. Of these, 377 (15.2%) patients had a MACE event and 203 (8.2%) were readmitted within 90 days from peak troponin measurement. A total of 1107 (44.5%) patients had an elevated troponin level. Of 1107 patients with elevated troponin at exacerbation, 256 (22.8%) had a MACE event and 101 (9.0%) a COPD readmission within 90 days from peak troponin measurement. Patients with troponin above the upper limit of normal had a higher risk of MACE (adjusted HR 2.20, 95% CI 1.75-2.77) and COPD hospital readmission (adjusted HR 1.37, 95% CI 1.02-1.83) when compared with patients without elevated troponin. Conclusion: An elevated troponin level at the time of COPD exacerbation may be a useful tool for predicting MACE in COPD patients. The relationship between degree of troponin elevation and risk of future events is complex and requires further investigation.
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Enfermedades Cardiovasculares , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Readmisión del Paciente , Hospitalización , Troponina , Enfermedades Cardiovasculares/etiologíaRESUMEN
Mechanisms that control mRNA metabolism are critical for cell function, development and stress response. The Saccharomyces cerevisiae mRNA-binding protein Ssd1 has been implicated in mRNA processing, ageing, stress response and maintenance of cell integrity. Ssd1 is a substrate of the LATS/NDR tumour suppressor orthologue Cbk1 kinase. Previous data indicate that Ssd1 localizes to the cytoplasm; however, biochemical interactions suggest that Ssd1 at least transiently localizes to the nucleus. We therefore explored whether nuclear localization is important for Ssd1 cytoplasmic functions. We identified a functional NLS in the N-terminal domain of Ssd1. An Ssd1-derived NLS-GFP fusion protein and several C-terminally truncated Ssd1 proteins, which presumably lack nuclear export sequences, accumulate in the nucleus. Alanine substitution of the Ssd1 NLS prevents Ssd1 nuclear entry, mRNA binding and disrupts Srl1 mRNA localization. Moreover, Ssd1-NLS mutations abolish Ssd1 toxicity in the absence of Cbk1 phosphorylation and cause Ssd1 to localize prominently to cytoplasmic puncta. These data indicate that nuclear shuttling is critical for Ssd1 mRNA binding and Ssd1-mRNA localization in the cytoplasm. Collectively these data support the model that Ssd1 functions analogously to hnRNPs, which bind mRNA co-transcriptionally, are exported to the cytoplasm and target mRNAs to sites of localized translation and P-bodies.
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Núcleo Celular/metabolismo , Citoplasma/metabolismo , Regulación Fúngica de la Expresión Génica , ARN Mensajero/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transporte Activo de Núcleo Celular , Fusión Artificial Génica , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Modelos Biológicos , Mutagénesis Sitio-Dirigida , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Señales de Localización Nuclear , Proteínas de Saccharomyces cerevisiae/genética , Eliminación de SecuenciaRESUMEN
Like all ciliates, Paramecium tetraurelia is a unicellular eukaryote that harbors two kinds of nuclei within its cytoplasm. At each sexual cycle, a new somatic macronucleus (MAC) develops from the germ line micronucleus (MIC) through a sequence of complex events, which includes meiosis, karyogamy, and assembly of the MAC genome from MIC sequences. The latter process involves developmentally programmed genome rearrangements controlled by noncoding RNAs and a specialized RNA interference machinery. We describe our first attempts to identify genes and biological processes that contribute to the progression of the sexual cycle. Given the high percentage of unknown genes annotated in the P. tetraurelia genome, we applied a global strategy to monitor gene expression profiles during autogamy, a self-fertilization process. We focused this pilot study on the genes carried by the largest somatic chromosome and designed dedicated DNA arrays covering 484 genes from this chromosome (1.2% of all genes annotated in the genome). Transcriptome analysis revealed four major patterns of gene expression, including two successive waves of gene induction. Functional analysis of 15 upregulated genes revealed four that are essential for vegetative growth, one of which is involved in the maintenance of MAC integrity and another in cell division or membrane trafficking. Two additional genes, encoding a MIC-specific protein and a putative RNA helicase localizing to the old and then to the new MAC, are specifically required during sexual processes. Our work provides a proof of principle that genes essential for meiosis and nuclear reorganization can be uncovered following genome-wide transcriptome analysis.
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Macronúcleo/metabolismo , Micronúcleo Germinal/metabolismo , Paramecium tetraurelia/metabolismo , Proteínas Protozoarias/metabolismo , Autofecundación , Regulación del Desarrollo de la Expresión Génica , Macronúcleo/genética , Micronúcleo Germinal/genética , Paramecium tetraurelia/genética , Paramecium tetraurelia/crecimiento & desarrollo , Proteínas Protozoarias/genéticaRESUMEN
Purpose: Dabrafenib and trametinib combination therapy (dab + tram) is indicated to treat BRAF V600 mutation-positive unresectable/metastatic melanoma and as adjuvant treatment for resected stage III disease. Dab + tram-related pyrexia may require early therapy discontinuation. A modified Delphi panel was conducted to develop consensus on the optimal management of dab + tram-related pyrexia in patients with melanoma. Methods: In all, 10 UK oncologists experienced in melanoma management participated in a three-round modified Delphi study (Round 1: one-to-one interview; Rounds 2 and 3: email survey). In each round, participants rated the extent of their agreement with statements about defining and managing dab + tram-related pyrexia. Consensus was defined as >80% agreement for critical management (CM) and >60% for non-critical management (NCM) statements. Results: All 10 participants completed Round 1; 9 completed Rounds 2 and 3. Consensus was reached on 42/66 statements (20 CM and 22 NCM). Drug-related pyrexia was agreed as being strictly an elevation of body temperature, although other symptoms may be present (89% agreement). Panelists agreed on the need for simple and generic guidance on dab + tram-related pyrexia management that does not differentiate between patient groups (100%), and that management of first and second dab + tram-related pyrexia episodes should be the same regardless of treatment intent (100%). Regarding CM, participants agreed that both dab and tram should be interrupted for pyrexia (100%) without considering the use of steroids (89%); patients on dab + tram presenting to non-oncology services with pyrexia should be directed to an oncology-specific service as soon as possible and assessed for infection (100%). NCM statements on steroid use following dab + tram interruption and when to restart dab + tram did not reach consensus. Conclusions: These consensus statements provide a framework on optimal management of dab + tram-related pyrexia in patients with melanoma which should inform future guidelines.
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The treatment of metastatic melanoma has been revolutionised with the emergence of checkpoint inhibitors. The combination of Ipilimumab and Nivolumab offers the longest overall survival but is considerably more toxic than single-agent therapy. For patients who received single-agent immunotherapy it is unclear whether second-line immunotherapy is efficacious or tolerable. This study looked at outcomes for patients treated with sequential immunotherapy and compared them to patients who received dual immunotherapy. Fifty-eight patients received both Ipilimumab and an anti-PD-1 agent during the 5-year period, twenty-seven received dual immunotherapy, twenty received first-line Ipilimumab and eleven received an anti-PD-1 agent first line. The median overall survival (OS) was 24.8 months. The 5 year survival was greatest in patients treated with dual immunotherapy (42%) compared to first-line anti-PD-1 (33.3%) and first-line Ipilimumab (0%). As second-line treatments, anti-PD-1 agents had a median OS of 16.5 months compared to Ipilimumab at 3.4 months. 77.8% of patients had grade 3/4 toxicity with dual immunotherapy compared to 10% of patients treated with first-line Ipilimumab and 0% with anti-PD-1 agents. In the second line, 72.7% of patients treated with Ipilimumab experienced grade 3/4 toxicity, compared to 20% of patients treated with second-line anti-PD-1 agents. This study suggests Ipilimumab is not efficacious in patients who progress after anti-PD-1 agents, and this sequential approach does not avoid toxicity. The emergence of new checkpoint inhibitors will hopefully provide more efficacious treatment options for patients unable to tolerate Ipilimumab.
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Inmunoterapia/métodos , Melanoma/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Melanoma/patología , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Cutáneas/patologíaRESUMEN
Treatments for melanoma have significantly advanced with the approval of targeted treatments against the BRAF/MEK pathway and immunotherapy in the form of checkpoint inhibitors. Studies have shown the effectiveness of these treatments against brain metastases. However, the optimum treatment strategy utilising CNS-directed treatments such as stereotactic radiosurgery (SRS) and neurosurgical resection is less clear. Over six years, 70 patients with metastatic melanoma were treated for brain metastases at a tertiary treatment centre. The median overall survival (OS) for all patients was 10.2 months. 51 patients received localised treatment; 7 resection (median OS 10 months), 11 resection and SRS (median OS 17.3 months) and 33 SRS alone (median OS 17.4 months). For patients treated with SRS those who had <2 cm3 treated had a better median OS (20.5 months) compared to those who had >2 cm3 treated (12 months). 69 Patients received systemic treatment. The median OS of patients who did not have CNS-directed treatment was poor (median OS 1.2 months). Patients treated with first line dual immunotherapy had the best median OS (26.7 months), compared to anti-PD-1 (14.1 months), ipilimumab (14.3 months) and kinase inhibitors (10.9 months). Despite advancements in treatment, the development of brain metastases in melanoma is associated with worse outcomes. A combination of CNS-directed and systemic treatment is important to improve survival. Dual immunotherapy appears to be the most effective systemic treatment and the use of SRS improved outcomes. As metastatic melanoma treatments evolve there need to be an ongoing focus to ensure these strategies adequately treat intracranial disease.
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In Saccharomyces cerevisiae, the RAM network is involved in cell separation after cytokinesis, cell integrity and cell polarity. The key function of this network is the regulation of the activity of the protein kinase Cbk1p, which is a member of the conserved NDR kinase family. Cbk1p function is controlled by its sub-cellular localization and at least two phosphorylation events: an auto phosphorylation in the kinase domain (S570) and the phosphorylation of a C-terminal hydrophobic motif by an upstream kinase (T743). After a UV mutagenesis, we have isolated 115 independent extragenic suppressors of four ram mutations: tao3, hym1, kic1 and sog2. Over 50% of the suppressors affect a single residue in Cbk1p (S745F), which is close to the phosphorylation site in the hydrophobic motif. Our results show that the CBK1-S745F allele leads to a constitutively active form of Cbk1p that is independent of the upstream RAM network. We hypothesize that the mutant Cbk1-S745Fp mimics the effect of the phosphorylation of T743.
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Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimología , Proteínas Adaptadoras Transductoras de Señales/genética , Sustitución de Aminoácidos , Polaridad Celular , Secuencia Conservada , Proteínas de Unión al ADN/metabolismo , Activación Enzimática/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Redes y Vías Metabólicas , Mutación , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Estructura Terciaria de Proteína/genética , Proteínas Represoras/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo , Proteínas de Saccharomyces cerevisiae/genética , Supresión Genética , Factores de Transcripción/metabolismoRESUMEN
AIM: The Ilizarov external fixator (IEF) is frequently used in trauma and elective orthopaedics. Many of its biomechanical variables (ring size, wire diameter, wire number, half pins vs wires, etc.) and their influence on stability and stiffness have been investigated. There is, however, a paucity in the literature regarding the influence of the connecting rod numbers and configurations between the rings on IEF stability. The primary aim of this biomechanical study was to compare the stability between four- and three-rod IEF configurations. Secondarily to assess the difference in stability between symmetrical and asymmetrical spacing of the IEF rods. MATERIALS AND METHODS: A custom jig was designed to facilitate mounting of a basic two-ring IEF in a hydraulic press. Controlled centre and off-centre (thus simulated bending) axial loading was then applied across the frame. The configurations were loaded up to 4,000 N. The frame deformation was plotted and the data were then analysed and interpreted. RESULTS: Negligible differences were observed between different four- and three-rod configurations as long as the applied force at the loading point (LP) was within the area of support (AOS) created by the rods. The different four-rod constructs were always more stable than the three-rod constructs during bending. CONCLUSION: There is comparable stiffness between a four-rod and a three-rod IEF construct as long as the LP is within the AOS created by the rods. A four-rod IEF is stiffer than a three-rod IEF in bending. CLINICAL SIGNIFICANCE: This study will possibly change some paradigms regarding the planning and application of IEFs by Orthopaedics Traumatologists and Reconstruction Surgeons. HOW TO CITE THIS ARTICLE: Thiart G, Herbert C, Sivarasu S, et al. Influence of Different Connecting Rod Configurations on the Stability of the Ilizarov/TSF Frame: A Biomechanical Study. Strategies Trauma Limb Reconstr 2020;15(1):23-27.
RESUMEN
BACKGROUND INFORMATION: The CBK1 gene of Saccharomyces cerevisiae encodes a protein kinase that is a member of the NDR (nuclear Dbf2-related) family of protein kinases, which are involved in morphogenesis and cell proliferation. Previous studies have shown that deletion of CBK1 leads to a loss of polarity and the formation of large aggregates of cells. This aggregation phenotype is due to the loss of the daughter cell-specific accumulation of the transcription factor Ace2p, which is responsible for the transcription of genes whose products are necessary for the final separation of the mother and the daughter at the end of cell division. RESULTS: We show that the daughter cell-specific localization of Ace2p does not occur via a specific localization of the ACE2 mRNA and that, in vivo, the transcription of CTS1, one of the principal targets of Ace2p, is daughter cell-specific. We have shown that extragenic suppressors of the Deltacbk1 aggregation phenotype are located in the nuclear exportin CRM1 and ACE2. These mutations disrupt the interaction of Ace2p and Crm1p, thus impairing Ace2p export and resulting in the accumulation of the protein in both mother and daughter cell nuclei. CONCLUSIONS: We propose that in the daughter cell nucleus Cbk1p phosphorylates the Ace2p nuclear export signal, and that this phosphorylation blocks the export of Ace2p via Crm1p, thus promoting the daughter cell-specific nuclear accumulation of Ace2p.
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Núcleo Celular/metabolismo , Proteínas de Unión al ADN/metabolismo , Carioferinas/genética , Mutación , Receptores Citoplasmáticos y Nucleares/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Transporte Activo de Núcleo Celular , División Celular , Núcleo Celular/genética , Quitinasas/genética , Proteínas de Unión al ADN/análisis , Proteínas de Unión al ADN/genética , Proteínas Fúngicas/análisis , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Carioferinas/metabolismo , Proteínas Serina-Treonina Quinasas , Transporte de Proteínas , Receptores Citoplasmáticos y Nucleares/metabolismo , Proteínas Represoras/análisis , Proteínas Represoras/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/análisis , Proteínas de Saccharomyces cerevisiae/genética , Especificidad de la Especie , Factores de Transcripción/análisis , Factores de Transcripción/genética , Proteína Exportina 1RESUMEN
The rapid growth of the US population ages seventy-five and older in the coming years will increase the need for housing that accommodates mobility limitations and helps connect residents with supportive services and opportunities for socialization. While expanding the supply of housing with services such as those provided by independent and assisted living facilities is needed, so too are greater supports to allow older adults with disabilities to age successfully in their homes and communities. These include financial support for modifications to the home, the delivery of supportive services in the home by both family and paid caregivers, and the expansion of housing options in communities where older adults live.
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Envejecimiento Saludable , Vida Independiente , Apoyo Social , Anciano , Anciano de 80 o más Años , Humanos , Política Pública , Estados UnidosRESUMEN
AIM OF STUDY: The aim of the study was to assess the impact of treatment with adjuvant vemurafenib monotherapy on health-related quality of life (HRQOL) in patients with resected stage IIC-IIIC melanoma. METHODS: The phase 3 BRIM8 study (NCT01667419) randomised patients with BRAFV600 mutation-positive resected stage IIC-IIIC melanoma to 960 mg of vemurafenib twice daily or matching placebo for 52 weeks (13 × 28-day cycles). Patients completed the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) version 3 at baseline, cycle 1 (days 1, 15 and 22), cycle 2 (days 1 and 15), day 1 of every subsequent 4-week cycle, the end-of-treatment visit and each visit during the follow-up period. RESULTS: Completion rates for the EORTC QLQ-C30 questionnaire were high (>80%). There was a mean decline in the global health status (GHS)/quality of life (QOL) score of 17.4 (±22.9) and 17.3 (±24.1) points at days 15 and 22 of cycle 1, respectively, among vemurafenib-treated patients who recovered to approximately 10 points below baseline for the remainder of the treatment period. A similar trend was observed in all functional scales except for cognitive function (<10-point change from baseline at all visits) and in the symptom scores for appetite loss, fatigue and pain. As observed for the GHS/QOL score, all scores rapidly returned to baseline after completion of planned vemurafenib treatment or treatment discontinuation. CONCLUSIONS: The schedule of HRQOL assessments allowed for an accurate and complete evaluation of the impact of acute treatment-related symptoms. Vemurafenib-treated patients experience clinically meaningful moderate worsening in some treatment- or disease-related symptoms and GHS/QOL that resolve over time.