RESUMEN
EWS is a member of the FET family of RNA/DNA binding proteins that regulate crucial phases of nucleic acid metabolism. EWS comprises an N-terminal low-complexity domain (LCD) and a C-terminal RNA-binding domain (RBD). The RBD is further divided into three RG-rich regions, which flank an RNA-recognition motif (RRM) and a zinc finger (ZnF) domain. Recently, EWS was shown to regulate R-loops in Ewing sarcoma, a pediatric bone and soft-tissue cancer in which a chromosomal translocation fuses the N-terminal LCD of EWS to the C-terminal DNA binding domain of the transcription factor FLI1. Though EWS was shown to directly bind R-loops, the binding mechanism was not elucidated. In the current study, the RBD of EWS was divided into several constructs, which were subsequently assayed for binding to various nucleic acid structures expected to form at R-loops, including RNA stem-loops, DNA G-quadruplexes, and RNA:DNA hybrids. EWS interacted with all three nucleic acid structures with varying affinities and multiple domains contributed to binding each substrate. The RRM and RG2 region appear to bind nucleic acids promiscuously while the ZnF displayed more selectivity for single-stranded structures. With these results, the structural underpinnings of EWS recognition and binding of R-loops and other nucleic acid structures is better understood.
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Ácidos Nucleicos , Proteínas de Unión al ARN , Humanos , Niño , Proteína EWS de Unión a ARN/genética , Proteína EWS de Unión a ARN/química , Proteína EWS de Unión a ARN/metabolismo , Proteínas de Unión al ADN , ADN , ARN , Línea Celular TumoralRESUMEN
OBJECTIVES: High-energy Proton Beam Therapy (PBT) commenced in England in 2018 and NHS England commissions PBT for 1.5% of patients receiving radical radiotherapy. We sought expert opinion on the level of provision. METHODS: Invitations were sent to 41 colleagues working in PBT, most at one UK centre, to contribute by completing a spreadsheet. 39 responded: 23 (59%) completed the spreadsheet; 16 (41%) declined, arguing that clinical outcome data are lacking, but joined six additional site-specialist oncologists for two consensus meetings. The spreadsheet was pre-populated with incidence data from Cancer Research UK and radiotherapy use data from the National Cancer Registration and Analysis Service. 'Mechanisms of Benefit' of reduced growth impairment, reduced toxicity, dose escalation and reduced second cancer risk were examined. RESULTS: The most reliable figure for percentage of radical radiotherapy patients likely to benefit from PBT was that agreed by 95% of the 23 respondents at 4.3%, slightly larger than current provision. The median was 15% (range 4-92%) and consensus median 13%. The biggest estimated potential benefit was from reducing toxicity, median benefit to 15% (range 4-92%), followed by dose escalation median 3% (range 0 to 47%); consensus values were 12 and 3%. Reduced growth impairment and reduced second cancer risk were calculated to benefit 0.5% and 0.1%. CONCLUSIONS: The most secure estimate of percentage benefit was 4.3% but insufficient clinical outcome data exist for confident estimates. The study supports the NHS approach of using the evidence base and developing it through randomised trials, non-randomised studies and outcomes tracking. ADVANCES IN KNOWLEDGE: Less is known about the percentage of patients who may benefit from PBT than is generally acknowledged. Expert opinion varies widely. Insufficient clinical outcome data exist to provide robust estimates. Considerable further work is needed to address this, including international collaboration; much is already underway but will take time to provide mature data.
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Neoplasias Primarias Secundarias , Terapia de Protones , Terapia por Rayos X , Humanos , Neoplasias Primarias Secundarias/radioterapiaRESUMEN
Current research in radiotherapy (RT) for breast cancer is evaluating neoadjuvant as opposed to adjuvant partial breast irradiation (PBI) with the aim of reducing the volume of breast tissue irradiated and therefore the risk of late treatment-related toxicity. The development of magnetic resonance (MR)-guided RT, including dedicated MR-guided RT systems [hybrid machines combining an MR scanner with a linear accelerator (MR-linac) or 60Co sources], could potentially reduce the irradiated volume even further by improving tumour visibility before and during each RT treatment. In this position paper, we discuss MR guidance in relation to each step of the breast RT planning and treatment pathway, focusing on the application of MR-guided RT to neoadjuvant PBI.
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PURPOSE: Our purpose was to present and evaluate expert consensus on contouring primary breast tumors on magnetic resonance imaging (MRI) in the setting of neoadjuvant partial breast irradiation in trials. METHODS AND MATERIALS: Expert consensus on contouring guidelines for target definition of primary breast tumors on contrast-enhanced MRI in trials was developed by an international team of experienced breast radiation oncologists and a dedicated breast radiologist during 3 meetings. At the first meeting, draft guidelines were developed through discussing and contouring 2 cases. At the second meeting 6 breast radiation oncologists delineated gross tumor volume (GTV) in 10 patients with early-stage breast cancer (cT1N0) according to draft guidelines. GTV was expanded isotropically (20 mm) to generate clinical target volume (CTV), excluding skin and chest wall. Delineations were reviewed for disagreement and guidelines were clarified accordingly. At the third meeting 5 radiation oncologists redelineated 6 cases using consensus-based guidelines. Interobserver variation of GTV and CTV was assessed using generalized conformity index (CI). CI was calculated as the sum of volumes each pair of observers agreed upon, divided by the sum of encompassing volumes for each pair of observers. RESULTS: For the 2 delineation sessions combined, mean GTV ranged between 0.19 and 2.44 cm3, CI for GTV ranged between 0.28 and 0.77, and CI for CTV between 0.77 and 0.94. The largest interobserver variation in GTV delineations was observed in cases with extended tumor spiculae, blood vessels near or markers within the tumor, or with increased enhancement of glandular breast tissue. Consensus-based guidelines stated to delineate all visible tumors on contrast enhanced-MRI scan 1 to 2 minutes after contrast injection and if a marker was inserted in the tumor to include this. CONCLUSIONS: Expert-based consensus on contouring primary breast tumors on MRI in trials has been reached. This resulted in low interobserver variation for CTV in the context of a uniform 20 mm GTV to CTV expansion margin.
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Neoplasias de la Mama , Terapia Neoadyuvante , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/radioterapia , Consenso , Humanos , Imagen por Resonancia Magnética , Variaciones Dependientes del Observador , Planificación de la Radioterapia Asistida por Computador , Carga TumoralRESUMEN
Immobilized metal affinity chromatography (IMAC) is a specific high-capacity technique used in large-scale purification of proteins. IMAC exploits the ability of immobilized metal ions to form coordination bonds with atoms in the side chains of certain amino acids. The technique is generally robust. However, several factors still affect column binding capacity, retention, yield and purity of proteins during IMAC. It was observed that the recovery of 6× histidine, (His)6-tagged proteins from metal affinity columns differ significantly depending on the size of the protein. To test this observation, we determined the effect of protein size, flow-rate, number and position of (His)6 tag on the retention of highly expressing proteins on commercial Ni2+ and Co2+ IMAC columns. All experiments were performed in phosphate buffer to eliminate interference of amine-containing buffers with the binding of the (His)6 tag to the columns. Column retention was determined as the ratio of protein of interest in the supernatant (input) to flow-through (output). Data obtained suggest that regardless of the flow-rate, (His)6 tag position and number, the size of protein is a major factor affecting column retention and therefore recovery during column IMAC purification. Small and medium-sized proteins (~ 50 kDa) have higher column retention than bigger proteins, resulting in higher recovery. These outcomes provide important information to consider when performing IMAC.
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Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/aislamiento & purificación , Caenorhabditis elegans/química , Cromatografía de Afinidad , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/aislamiento & purificación , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Peso Molecular , Proteínas Recombinantes de Fusión/genéticaRESUMEN
There are numerous surgical approaches for oro-antral-fistula (OAF) closure. Secondary sinus disease is still considered by many experts a relative contra indication for primary closure. To describe a single-stage combined endoscopic sinus surgery and per-oral buccal fat pad (BFP) flap approach for large OAF causing chronic maxillary sinusitis. The records of all the patients with OAF and chronic manifestations of secondary rhinosinusitis that were treated between 2010 and 2013 in our tertiary care medical center were reviewed. The exclusion criteria were: OAF 5 mm, resolved sino-nasal disease, OAF secondary to malignancy, recurrent fistula, medical history that included radiotherapy to the maxillary bone and age <18 years. Each procedure was performed by a team consisting of a rhinologist and a maxillofacial surgeon. The surgical approach included an endoscopic middle antrostomy with maxillary sinus drainage, and a per-oral BFP regional flap for OAF closure. Total OAF closure, complications and need for revision surgeries. Forty-five patients that underwent OAF closure together with sinus surgery using a combined endoscopic sinus surgery (ESS) and BFP flap approach met the inclusion criteria. There were 28 males and 17 females with a mean ± SD age of 53.5 ± 14.9 years (range 22-80 years). The presenting signs and symptoms included purulent rhinorrhea (n = 22, 48.9%), foreign body in sinus (n = 10, 22.2%) nasal congestion (n = 7, 15.5%), halitosis (n = 6, 13.3%) and pain (n = 5, 12.2%). Surgical complications included local pain (n = 2, 4.4%), persistent rhinitis (n = 2, 4.4%) and synechia (n = 1, 2.2%). One patient required revision surgery due, to an unresolved OAF. The OAF of all the other 44 patients (97.8%) was closed after the first procedure and the paranasal sinuses on the treated side were completely recovered. The mean follow-up time for the group was 7.6 ± 4.3 months (7-21 months), and no untoward sequelae or recurrence were reported. Combined, one step, endoscopic Maxillary sinus drainage together with per-oral BFP flap approach is an efficacious surgical approach for safe closure of OAFs that are complicated with secondary chronic maxillary sinusitis.
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Endoscopía/métodos , Sinusitis Maxilar/cirugía , Fístula Oroantral/cirugía , Colgajos Quirúrgicos , Adulto , Anciano , Anciano de 80 o más Años , Mejilla/cirugía , Enfermedad Crónica , Drenaje/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Sinusitis Maxilar/etiología , Persona de Mediana Edad , Fístula Oroantral/complicaciones , Resultado del Tratamiento , Adulto JovenRESUMEN
Bowel toxicity is a major complication of cancer treatment, and its accurate reporting is important for assessing outcomes. The NCI's Common Terminology Criteria for Adverse Events (CTCAE) is the preferred method for capturing adverse events after all cancer treatments, particularly within clinical trials. However, the CTCAE version 4 does not include urgency of defecation as an item, despite this being one of the most common and persistent adverse consequences of treatment of pelvic cancers. The importance of bowel urgency to patients is well documented, and this treatment effect has a negative impact on social function and quality of life. Bowel urgency is also important clinically because it may represent significant underlying problems. This article presents the case for including patient reported assessment of bowel urgency as an independent item in cancer treatment adverse event reporting.
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Intestino Neurogénico/etiología , Neoplasias Pélvicas/complicaciones , Radioterapia/efectos adversos , Femenino , Humanos , Incidencia , Masculino , Intestino Neurogénico/epidemiología , Neoplasias Pélvicas/radioterapia , Autoinforme , Resultado del TratamientoRESUMEN
STUDY TYPE: Preference (prospective cohort). LEVEL OF EVIDENCE: 1b. What's known on the subject? and What does the study add? In general the literature suggests that there is a need for improvement in aiding men diagnosed with early prostate cancer in their decision making about treatment options and that our understanding of this process is inadequate. There is limited data analyzing the reasons why these men decide between potentially curative or observational treatments and data evaluating patients' views before and after definitive therapy are scarce. This study begins the process of understanding the reasons underlying a patient's final treatment decision. Being a prospective study, it looks at the thought processes of these men before treatment during the time the decision is made. It also documents how satisfied patients are with their choice after their treatment and whether they would choose the same treatment again. OBJECTIVE: To identify the reasons for patients with localised prostate cancer choosing between treatments and the relationship of procedure type to patient satisfaction post-treatment. PATIENTS AND METHODS: 768 men with prostate cancer (stage T1/2, Gleason≤7, PSA<20 ug/L) chose between four treatments: radical prostatectomy, brachytherapy, conformal radiotherapy and active surveillance. Prior to choosing, patients were counselled by a urological surgeon, clinical (radiation) oncologist and uro-oncology specialist nurse. Pre-treatment reasons for choice were recorded. Post-treatment satisfaction was examined via postal questionnaire. RESULTS: Of the 768 patients, 305 (40%) chose surgery, 237 (31%) conformal beam radiotherapy, 165 (21%) brachytherapy and 61 (8%) active surveillance. Sixty percent of men who opted for radical prostatectomy were motivated by the need for physical removal of the cancer. Conformal radiotherapy was mainly chosen by patients who feared other treatments (n=63, 27%). Most men chose brachytherapy because it was more convenient for their lifestyle (n=64, 39%). Active surveillance was chosen by patients for more varied reasons. Post-treatment satisfaction was assessed in a subgroup who took part in the QOL aspect of this study. Of the respondents to the questionnaire, 212(87.6%) stated that they were satisfied/extremely satisfied with their choice and 171(92.9%) indicated they would choose the same treatment again. CONCLUSION: Men with early prostate cancer have clear reasons for making decisions about treatment. Overall, patients were satisfied with the treatment and indicated that despite different reasons for choosing treatment, they would make the same choice again.
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Braquiterapia/tendencias , Observación/métodos , Prostatectomía/tendencias , Neoplasias de la Próstata/terapia , Radioterapia Conformacional/tendencias , Adulto , Factores de Edad , Anciano , Braquiterapia/métodos , Estudios de Cohortes , Toma de Decisiones , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Prioridad del Paciente , Estudios Prospectivos , Prostatectomía/métodos , Neoplasias de la Próstata/patología , Radioterapia Conformacional/métodos , Medición de Riesgo , Encuestas y Cuestionarios , Reino UnidoRESUMEN
The mechanism of increased ferritin synthesis in inflammation was studied in rat livers 0-48 h after turpentine injection. A subcellular protein synthesizing system was employed in which the respective roles of cell sap factors and polysomes from normal and treated animals could be studied. Two waves of increased ferritin synthesis were found, an early wave with peak activity at 6 h of inflammation, and a second wave starting at about 24 h. The early wave of enhanced ferritin synthesis was associated with increased activity of cell sap factors. In contrast, the late enhancement of ferritin synthesis was characterized by increased polysomal activity as well as increased cell sap activity. These observations suggest a post-transcriptional control mechanism for the early phase of enhanced ferritin synthesis in inflammation, and a transcriptional as well as post-transcriptional control for the late phase of enhanced ferritin synthesis.
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Ferritinas/biosíntesis , Hepatitis Animal/metabolismo , Albúminas/biosíntesis , Animales , Apoferritinas/biosíntesis , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Hemopexina/biosíntesis , Leucina/metabolismo , Hígado/metabolismo , Masculino , Ratas , Ratas Endogámicas , Factores de Tiempo , TrementinaRESUMEN
The growth of transplantable tumors, both in the solid and ascites form, was associated with a concomitant elevation of plasma hemopexin (HPX). A study of the dynamics of HPX concentrations in plasma, tumor and urine of normal and tumor-bearing mice demonstrated that HPX elevation in the plasma did not result from a delayed clearance from the circulation or body. Neither the plasma disappearance curve of i.v. (125I)HPX nor the urinary excretion of its metabolites was affected by the presence of the tumors. A body half life of about 8 h was found for both tumors-bearing and control mice. It was calculated that the presence of tumors caused a 9- to 18-fold increase of HPX concentration in the animal, which was probably the result of an accelerated synthesis. Some accumulation of HPX was found in solid tumors, both by traces of radioiodinated HPX and quantitative determination of endogenous HPX. In the case of ascites tumor, no HPX could be detected in the tumor cells.
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Hemopexina/metabolismo , Neoplasias Experimentales/metabolismo , Animales , Semivida , Hemopexina/inmunología , Hemopexina/orina , Radioisótopos de Yodo , Ratones , Trasplante de Neoplasias , Factores de Tiempo , Trasplante HomólogoRESUMEN
The effect of carbohydrate free-low protein diets on the redox potential and ketone body concentrations in liver, muscle, and blood was investigated. Two carbohydrate free diets were fed: 1) A diet in which all the non-protein energy was provided by fatty acids (FA); 2) A similar diet in which the fatty acids were substituted by neutral fat (NF). A carbohydrate rich diet (HC) was fed for comparison. The redox potentials in cytoplasma and mitochondria were calculated from the relative concentrations of the [lactate]:[pyruvate] and [beta-hydroxy-butyrate]:[acetoacetate] couples respectively. In fed rats the cytoplasmic redox potential in liver was much higher in FA than in NF rats, but in fasted NF rats it increased markedly and equaled that of FA rats. In liver mitochondria the redox potential was lower in fed FA than in fed NF rats, while after a 24 hour fast it increased in FA rats and decreased in NF rats. Total ketone body concentrations were high in fed NF rats and increased further in fasted rats, however, in FA rats the high concentrations in the fed state decreased after the short fast. The changes of total ketone-bodies in blood and muscle followed those in liver in both fed and fasted states.
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Carbohidratos/deficiencia , Cuerpos Cetónicos/metabolismo , Acetoacetatos/metabolismo , Animales , Citoplasma/metabolismo , Carbohidratos de la Dieta , Grasas de la Dieta , Metabolismo Energético , Ayuno , Ácidos Grasos , Hidroxibutiratos/metabolismo , Lactatos/metabolismo , Hígado/metabolismo , Masculino , Músculos/metabolismo , NAD/metabolismo , Oxidación-Reducción , Deficiencia de Proteína/metabolismo , Piruvatos/metabolismo , RatasRESUMEN
Insulin-carbohydrate relationships were investigated in four groups of young rats fed low protein diets differing in carbohydrate and fat contents: (1) a diet in which the nonprotein energy was provided by fatty acids (FA); (2) a similar diet in which the fatty acids were substituted by neutral fat (NF); (3) FA diet supplemented with glycerol (FA-Glyc); and (4) a carbohydrate-rich diet (HC). Control rats were fed a stock diet. Rats fed the FA diet lost weight, were hypoglycemic and hypoinsulinemic in the fed state and normoglycemic and normoinsulinemic in the fasted state, and had an impaired glucose tolerance and hyperinsulinemia after a glucose load. Liver and muscle glycogen were low in fed rats. Fasting increased glycogen in liver and decreased glycogen in muscle. NF animals gained weight, were hypoglycemic in both fed and fasted states, and their plasma glucose level after an oral glucose load was almost normal. Plasma insulin/glucose ratio, both in fed and fasted states and after a glucose load indicated hyperinsulinism, which was accompanied by obesity. Muscle and liver glycogen were low in fed animals and did not change after a fast. Supplementation of the FA diet with glycerol (FA-Glyc) abolished weight loss and fasting hyperglycemia and normalized plasma glucose and insulin response to a glucose load. Rats fed the HC diet had an improved glucose tolerance and an increased sensitivity to insulin. Liver glycogen was high in the fed state and normal in the fasted state, whereas muscle glycogen was normal in both nutritional states.