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1.
Genes Dev ; 32(17-18): 1252-1265, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30108132

RESUMEN

The transcriptional coactivators Mediator and two histone acetyltransferase (HAT) complexes, NuA4 and SAGA, play global roles in transcriptional activation. Here we explore the relative contributions of these factors to RNA polymerase II association at specific genes and gene classes by rapid nuclear depletion of key complex subunits. We show that the NuA4 HAT Esa1 differentially affects certain groups of genes, whereas the SAGA HAT Gcn5 has a weaker but more uniform effect. Relative dependence on Esa1 and Tra1, a shared component of NuA4 and SAGA, distinguishes two large groups of coregulated growth-promoting genes. In contrast, we show that the activity of Mediator is particularly important at a separate, small set of highly transcribed TATA-box-containing genes. Our analysis indicates that at least three distinct combinations of coactivator deployment are used to generate moderate or high transcription levels and suggests that each may be associated with distinct forms of regulation.


Asunto(s)
Regulación Fúngica de la Expresión Génica , Histona Acetiltransferasas/fisiología , Complejo Mediador/fisiología , Proteínas de Saccharomyces cerevisiae/fisiología , Saccharomyces cerevisiae/genética , Activación Transcripcional , Acetilación , Histonas/metabolismo , Complejo Mediador/metabolismo , Estrés Oxidativo/genética , Regiones Promotoras Genéticas , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteína de Unión a TATA-Box/metabolismo , Transcripción Genética
2.
Support Care Cancer ; 32(6): 331, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710920

RESUMEN

AIM: We evaluated the efficacy and safety of Nuvastatic™ (C5OSEW5050ESA) in improving cancer-related fatigue (CRF) among cancer patients. METHODS: This multicenter randomized double-blind placebo-controlled phase 2 trial included 110 solid malignant tumor patients (stage II-IV) undergoing chemotherapy. They were randomly selected and provided oral Nuvastatic™ 1000 mg (N = 56) or placebo (N = 54) thrice daily for 9 weeks. The primary outcomes were fatigue (Brief Fatigue Inventory (BFI)) and Visual Analog Scale for Fatigue (VAS-F)) scores measured before and after intervention at baseline and weeks 3, 6, and 9. The secondary outcomes were mean group difference in the vitality subscale of the Medical Outcome Scale Short Form-36 (SF-36) and urinary F2-isoprostane concentration (an oxidative stress biomarker), Eastern Cooperative Oncology Group scores, adverse events, and biochemical and hematologic parameters. Analysis was performed by intention-to-treat (ITT). Primary and secondary outcomes were assessed by two-way repeated-measures analysis of variance (mixed ANOVA). RESULTS: The Nuvastatic™ group exhibited an overall decreased fatigue score compared with the placebo group. Compared with the placebo group, the Nuvastatic™ group significantly reduced BFI-fatigue (BFI fatigue score, F (1.4, 147) = 16.554, p < 0.001, partial η2 = 0.333). The Nuvastatic™ group significantly reduced VAS-F fatigue (F (2, 210) = 9.534, p < 0.001, partial η2 = 0.083), improved quality of life (QoL) (F (1.2, 127.48) = 34.07, p < 0.001, partial η2 = 0.243), and lowered urinary F2-IsoP concentrations (mean difference (95% CI) = 55.57 (24.84, 86.30)), t (55) = 3.624, p < 0.001, Cohen's d (95% CI) = 0.48 (0.20, 0.75)). Reported adverse events were vomiting (0.9%), fever (5.4%), and headache (2.7%). CONCLUSION: Nuvastatic™ is potentially an effective adjuvant for CRF management in solid tumor patients and worthy of further investigation in larger trials. TRIAL REGISTRATION: ClinicalTrial.gov ID: NCT04546607. Study registration date (first submitted): 11-05-2020.


Asunto(s)
Cinamatos , Depsidos , Fatiga , Neoplasias , Ácido Rosmarínico , Humanos , Método Doble Ciego , Fatiga/etiología , Fatiga/tratamiento farmacológico , Femenino , Persona de Mediana Edad , Masculino , Neoplasias/complicaciones , Anciano , Depsidos/farmacología , Depsidos/administración & dosificación , Depsidos/uso terapéutico , Adulto , Cinamatos/administración & dosificación , Cinamatos/uso terapéutico , Cinamatos/farmacología , Extractos Vegetales/administración & dosificación
3.
Am J Kidney Dis ; 81(6): 684-694.e1, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36587890

RESUMEN

RATIONALE & OBJECTIVE: The optimum starting dose of intravenous continuous erythropoietin receptor activator (C.E.R.A.) has been previously determined; this study ascertains the optimum starting dose of subcutaneous C.E.R.A. administration in pediatric patients. STUDY DESIGN: Phase 2, open-label, single-arm, multicenter study. SETTING & PARTICIPANTS: Patients aged 3 months to 17 years with renal anemia and chronic kidney disease (CKD; including those treated with maintenance dialysis and those not treated with dialysis) who were receiving maintenance treatment with erythropoiesis-stimulating agents (ESAs). INTERVENTION: Subcutaneous C.E.R.A. administration every 4 weeks (starting dose was based on defined conversion factors). OUTCOME: The primary outcome was the change in hemoglobin concentration between the baseline and evaluation period for each patient. Secondary efficacy measures and safety were also evaluated. RESULTS: Forty patients aged 0.4-17.7 years were enrolled. The study achieved its primary outcome: the mean change in hemoglobin concentration was an increase of 0.48g/dL; the 95% confidence interval (0.15-0.82) and standard deviation (±1.03) were within the prespecified boundaries (-1 to 1g/dL and<1.5g/dL, respectively). Mean hemoglobin concentrations were maintained within the target 10-12g/dL range in 24 of 38 patients and within±1g/dL of the baseline in 19 of 38 patients, and the median C.E.R.A. subcutaneous dose decreased over time. Efficacy in key subgroups (age group, dialysis type, prior ESA treatment) was consistent with the primary outcome. Thirty-eight patients completed the core period; 25 chose to enter the safety extension period. Safety was consistent with prior studies, with no new signals. LIMITATIONS: Single-arm and open-label study; small sample size. CONCLUSIONS: Pediatric patients with anemia secondary to CKD who were on, or not on, dialysis could be safely and effectively switched from maintenance ESAs to subcutaneous C.E.R.A. administered every 4 weeks, using defined dose-conversion factors to determine the optimum starting dose. FUNDING: F. Hoffmann-La Roche Ltd. TRIAL REGISTRATION: The SKIPPER trial registered at ClinicalTrials.gov with study number NCT03552393. PLAIN-LANGUAGE SUMMARY: Anemia, a complication of chronic kidney disease, is associated with poor quality of life and an increased risk of hospitalization and mortality. The current treatments for anemia include iron therapy and erythropoiesis-stimulating agents (ESAs); however, the relatively short half-lives of the ESAs epoetin alfa/beta or darbepoetin alfa may require more frequent dosing and hospital visits compared with the ESA known as continuous erythropoietin receptor activator (C.E.R.A.). A previous study demonstrated that children aged 5 years or more with anemia associated with chronic kidney disease who were on hemodialysis could be switched to intravenous C.E.R.A. from their existing epoetin alfa/beta or darbepoetin alfa treatment. This study provides evidence that subcutaneous C.E.R.A. can safely and effectively treat anemia in children, including those aged<5 years and regardless of whether they were on dialysis or the type of dialysis they received (peritoneal dialysis or hemodialysis).


Asunto(s)
Anemia , Eritropoyetina , Hematínicos , Insuficiencia Renal Crónica , Humanos , Niño , Darbepoetina alfa/uso terapéutico , Epoetina alfa/uso terapéutico , Calidad de Vida , Eritropoyetina/uso terapéutico , Anemia/etiología , Anemia/complicaciones , Hematínicos/uso terapéutico , Insuficiencia Renal Crónica/terapia , Insuficiencia Renal Crónica/tratamiento farmacológico , Diálisis Renal/efectos adversos , Hemoglobinas
4.
Am J Kidney Dis ; 81(4): 434-445.e1, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36396085

RESUMEN

RATIONALE & OBJECTIVE: Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) are novel, orally administered agents for anemia management in chronic kidney disease (CKD). We evaluated the cardiac and kidney-related adverse effects of HIF-PHIs among patients with CKD and anemia. STUDY DESIGN: Systematic review and meta-analysis of randomized controlled trials (RCTs). SETTING & STUDY POPULATIONS: Patients with anemia and CKD not receiving maintenance dialysis. SELECTION CRITERIA FOR STUDIES: RCTs comparing HIF-PHIs to placebo or an erythropoiesis-stimulating agent (ESA) with primary outcomes of cardiac and kidney-related adverse events (AEs). DATA EXTRACTION: Two independent reviewers evaluated RCTs for eligibility and extracted relevant data. ANALYTICAL APPROACH: Dichotomous variables were pooled using the Mantel-Haenszel method and presented as risk ratios (RRs). Subgroup analyses evaluated different intervention times and HIF-PHIs, as well as phase 2 versus phase 3 trials. The certainty of findings was rated according to GRADE criteria. RESULTS: Twenty-three studies with 15,144 participants were included. No significant difference in the risk of cardiac AEs was observed between the HIF-PHIs group and the placebo (RR, 1.02 [95% CI, 0.89-1.16]; moderate certainty) or ESA (RR, 1.06 [95% CI, 0.98-1.14]; low certainty) groups. No significant difference in the risk of kidney-related AEs was observed between the HIF-PHIs group and the placebo (RR, 1.09 [95% CI, 0.98-1.20]; moderate certainty) or ESA (RR, 1.00 [95% CI, 0.94-1.06]; low certainty) groups. The occurrence of hypertension and hyperkalemia was higher in the HIF-PHIs group than in the placebo group (RRs of 1.35 [95% CI, 1.14-1.60] and 1.25 [95% CI, 1.03-1.51], respectively; both findings had high certainty). The occurrence of hypertension was lower in the HIF-PHIs group than in the ESA group (RR, 0.89 [95% CI, 0.81-0.98]; moderate certainty). LIMITATIONS: The reporting criteria of cardiac and kidney-related AEs and dosage of HIF-PHIs were inconsistent across trials. CONCLUSIONS: The occurrence of cardiac or kidney-related AEs in the HIF-PHI groups were not different compared with placebo or ESA groups. REGISTRATION: Registered at PROSPERO with registration number CRD42021228243.


Asunto(s)
Anemia , Hematínicos , Hipertensión , Inhibidores de Prolil-Hidroxilasa , Insuficiencia Renal Crónica , Humanos , Inhibidores de Prolil-Hidroxilasa/efectos adversos , Diálisis Renal/efectos adversos , Insuficiencia Renal Crónica/terapia , Insuficiencia Renal Crónica/tratamiento farmacológico , Anemia/tratamiento farmacológico , Hipertensión/tratamiento farmacológico , Hematínicos/efectos adversos , Riñón
5.
Am J Kidney Dis ; 81(2): 201-209.e1, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36181996

RESUMEN

RATIONALE & OBJECTIVE: Anemia is common in chronic kidney disease (CKD); although anemia is associated with adverse outcomes, the available treatments are not ideal. We characterized the burden, risk factors for, and risks associated with anemia by estimated glomerular filtration rate (eGFR) and hemoglobin level. STUDY DESIGN: Cross-sectional and prospective cohort study. SETTING & PARTICIPANTS: Outpatient data from 5,004,957 individuals across 57 health care centers in the United States from 2016 to 2019, extracted from the Optum Labs Data Warehouse. EXPOSURE: Severity of anemia, presence of low iron test results, eGFR. OUTCOME: Incident kidney failure with replacement therapy, cardiovascular disease, coronary heart disease, stroke, heart failure, death. ANALYTICAL APPROACH: The prevalences of anemia, low iron test results, vitamin B12 deficiency, and erythropoiesis-stimulating agent (ESA) use, stratified by sex and eGFR, were characterized. Polychotomous logistic regression was used to estimate the adjusted odds ratios of different hemoglobin levels across eGFR. Cox proportional hazards regression was used to calculate adjusted hazard ratios for adverse outcomes across hemoglobin level. RESULTS: The mean age was 54 years, and 42% were male. Lower eGFR was very strongly associated with increased prevalence of anemia, even after adjustment. Although iron studies were checked infrequently in patients with anemia, low iron test results were highly prevalent in those tested: 60.4% and 81.3% of men and women, respectively. ESA use was uncommon, with a prevalence of use of<4%. Lower hemoglobin was independently associated with increased risk of incident kidney failure with replacement therapy, cardiovascular disease, coronary heart disease, stroke, heart failure, and death. LIMITATIONS: Reliance on ICD codes for medical diagnoses, death information obtained from claims data, observational study. CONCLUSIONS: Severe anemia was common and strongly associated with lower eGFR and multiple adverse outcomes. Low-iron test results were highly prevalent in those tested despite iron studies being checked infrequently. ESA use in nondialysis CKD patients was uncommon.


Asunto(s)
Anemia , Insuficiencia Cardíaca , Hematínicos , Insuficiencia Renal Crónica , Accidente Cerebrovascular , Humanos , Masculino , Femenino , Estados Unidos/epidemiología , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Estudios Transversales , Anemia/complicaciones , Hematínicos/uso terapéutico , Insuficiencia Renal Crónica/diagnóstico , Hierro , Hemoglobinas , Riñón , Insuficiencia Cardíaca/complicaciones
6.
Clin Exp Nephrol ; 27(1): 79-88, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36100804

RESUMEN

BACKGROUND: Hyporesponsiveness to erythropoiesis-stimulating agents (ESAs) is associated with increased risks of all cause and cardiovascular mortality in patients undergoing hemodialysis (HD). However, the impact of the hematopoietic response to ESAs on the development of stroke, including brain hemorrhage and infarction, remains unclear. METHODS: In total, 2886 patients undergoing maintenance HD registered in the Q-Cohort Study who were treated with ESAs were prospectively followed up for 4 years. The hematopoietic response to ESAs was evaluated by the erythropoietin resistance index (ERI), calculated by dividing the weekly dose of ESA by post-HD weight and hemoglobin (U/kg/week/g/dL). The primary outcomes were the incidences of brain hemorrhage and infarction. Patients were divided into quartiles based on their ERI at baseline (Q1, ≤ 4.1; Q2, 4.2-7.0; Q3, 7.1-11.2; and Q4, ≥ 11.3). The risks of brain hemorrhage and infarction were estimated using Cox proportional hazards models, adjusting for potential confounders. RESULTS: During the 4 year follow-up period, 71 patients developed brain hemorrhage and 116 developed brain infarction. In the multivariable analysis, the incidence of brain hemorrhage in the highest quartile (Q4) was significantly higher than that in the lowest quartile (Q1) (hazard ratio [95% confidence interval], 2.18 [1.08-4.42]). However, the association between the ERI and the incidence of brain infarction was not significant. CONCLUSIONS: A higher ERI was associated with an increased risk of brain hemorrhage, but not brain infarction, in patients undergoing maintenance HD. A high ERI is thus an important risk factor for brain hemorrhage in these patients.


Asunto(s)
Anemia , Eritropoyetina , Hematínicos , Fallo Renal Crónico , Humanos , Hematínicos/uso terapéutico , Estudios de Cohortes , Eritropoyesis , Anemia/tratamiento farmacológico , Diálisis Renal/efectos adversos , Eritropoyetina/uso terapéutico , Hemorragias Intracraneales/inducido químicamente , Hemorragias Intracraneales/epidemiología , Hemorragias Intracraneales/complicaciones , Fallo Renal Crónico/terapia
7.
Sensors (Basel) ; 23(21)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37960592

RESUMEN

A Brain-Computer Interface (BCI) is a medium for communication between the human brain and computers, which does not rely on other human neural tissues, but only decodes Electroencephalography (EEG) signals and converts them into commands to control external devices. Motor Imagery (MI) is an important BCI paradigm that generates a spontaneous EEG signal without external stimulation by imagining limb movements to strengthen the brain's compensatory function, and it has a promising future in the field of computer-aided diagnosis and rehabilitation technology for brain diseases. However, there are a series of technical difficulties in the research of motor imagery-based brain-computer interface (MI-BCI) systems, such as: large individual differences in subjects and poor performance of the cross-subject classification model; a low signal-to-noise ratio of EEG signals and poor classification accuracy; and the poor online performance of the MI-BCI system. To address the above problems, this paper proposed a combined virtual electrode-based EEG Source Analysis (ESA) and Convolutional Neural Network (CNN) method for MI-EEG signal feature extraction and classification. The outcomes reveal that the online MI-BCI system developed based on this method can improve the decoding ability of multi-task MI-EEG after training, it can learn generalized features from multiple subjects in cross-subject experiments and has some adaptability to the individual differences of new subjects, and it can decode the EEG intent online and realize the brain control function of the intelligent cart, which provides a new idea for the research of an online MI-BCI system.


Asunto(s)
Interfaces Cerebro-Computador , Humanos , Electroencefalografía/métodos , Redes Neurales de la Computación , Imágenes en Psicoterapia , Electrodos , Algoritmos
8.
Medicina (Kaunas) ; 59(6)2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37374275

RESUMEN

Background and Objectives: Iron deficiency and anemia characterize patients on chronic hemodialysis (HD). Available intravenous iron agents, such as ferric gluconate (FG) and ferric carboxymaltose (FCM), vary in dosing regimens and safety profiles. The aim of the present study was to analyze the modification of the iron status, the correction of anemia, and the economic implications after the shift from FG to FCM therapy in chronic HD patients. We evaluated, during the study, the variations in iron metabolism, assessing ferritin and transferrin saturation, erythropoietin-stimulating agent (ESA) doses and the number of administrations, the effects on anemic status, and consequent costs. Materials and Methods: A retrospective study was performed with a follow-up period of 24 months, enrolling forty-two HD patients. The enrolment phase started in January 2015, when patients were treated with iv FG, and continued until December 2015, when FG was discontinued, and, after a wash-out period, the same patients were treated with FCM. Results: The iron switch reduced the administered dose of ESA by 1610.500 UI (31% of reduction; p < 0.001) during the entire study period and reduced the erythropoietin resistance index (ERI) (10.1 ± 0.4 vs. 14.8 ± 0.5; p < 0.0001). The FCM group had the highest percentage of patients who did not require ESA treatment during the study period. The FCM patients were characterized by higher levels of iron (p = 0.04), ferritin (p < 0.001), and TSAT levels (p < 0.001) compared to the FG patients. The annual cost during FG infusion was estimated at EUR 105,390.2, while one year of treatment with FCM had a total cost of EUR 84,180.7 (a difference of EUR 21,209.51 (20%), saving EUR 42.1 per patient/month (p < 0.0001). Conclusions: FCM was a more effective treatment option than FG, reducing ESA dose requirements, increasing Hb levels, and improving iron status. The reduced ESA doses and the decreased number of patients needing ESA were the main factors for reducing overall costs.


Asunto(s)
Anemia Ferropénica , Anemia , Eritropoyetina , Hematínicos , Humanos , Anemia/etiología , Anemia Ferropénica/tratamiento farmacológico , Eritropoyetina/metabolismo , Compuestos Férricos/uso terapéutico , Ferritinas , Hematínicos/uso terapéutico , Hierro/uso terapéutico , Diálisis Renal/efectos adversos , Estudios Retrospectivos
9.
Conserv Biol ; 36(3): e13851, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34668609

RESUMEN

Area of habitat (AOH) is defined as the "habitat available to a species, that is, habitat within its range" and is calculated by subtracting areas of unsuitable land cover and elevation from the range. The International Union for the Conservation of Nature (IUCN) Habitats Classification Scheme provides information on species habitat associations, and typically unvalidated expert opinion is used to match habitat to land-cover classes, which generates a source of uncertainty in AOH maps. We developed a data-driven method to translate IUCN habitat classes to land cover based on point locality data for 6986 species of terrestrial mammals, birds, amphibians, and reptiles. We extracted the land-cover class at each point locality and matched it to the IUCN habitat class or classes assigned to each species occurring there. Then, we modeled each land-cover class as a function of IUCN habitat with (SSG, using) logistic regression models. The resulting odds ratios were used to assess the strength of the association between each habitat and land-cover class. We then compared the performance of our data-driven model with those from a published translation table based on expert knowledge. We calculated the association between habitat classes and land-cover classes as a continuous variable, but to map AOH as binary presence or absence, it was necessary to apply a threshold of association. This threshold can be chosen by the user according to the required balance between omission and commission errors. Some habitats (e.g., forest and desert) were assigned to land-cover classes with more confidence than others (e.g., wetlands and artificial). The data-driven translation model and expert knowledge performed equally well, but the model provided greater standardization, objectivity, and repeatability. Furthermore, our approach allowed greater flexibility in the use of the results and uncertainty to be quantified. Our model can be modified for regional examinations and different taxonomic groups.


Conversión de la Categoría de Hábitat a Cobertura de Terreno para Mapear el Área de Hábitat de los Vertebrados Terrestres Resumen El área del hábitat (AOH) está definida como "el hábitat disponible para una especie, es decir, el hábitat dentro del área de distribución de la especie" y se calcula mediante la sustracción de las áreas de terreno inadecuado y la elevación del área de distribución. El Esquema de Clasificación de Hábitats de la Unión Internacional para la Conservación de la Naturaleza proporciona información sobre las asociaciones entre los hábitats de las especies y con frecuencia se utilizan las opiniones no validadas de expertos para cotejar el hábitat con los tipos de cobertura de terreno, lo que genera una fuente de incertidumbre en los mapas de AOH. Desarrollamos un método orientado por datos para convertir las categorías de hábitat que maneja la UICN en cobertura de terreno basado en los datos de localidad puntual de 6,986 especies de mamíferos terrestres, aves, anfibios y reptiles. Extrajimos la categoría de cobertura de terreno en cada localidad puntual y la cotejamos con la categoría o categorías de hábitat de UICN asignada a cada especie incidente en la localidad. Después modelamos cada categoría de cobertura de terreno como función del hábitat según la UICN usando modelos de regresión logística. Las proporciones de probabilidad resultantes fueron usadas para evaluar la solidez de la asociación entre cada categoría de hábitat y de cobertura de terreno. Después comparamos el desempeño de nuestro modelo orientado por datos con el desempeño de una tabla de conversión publicada basada en el conocimiento de expertos. Calculamos la asociación entre las categorías de hábitat y las de cobertura de terreno como una variable continua, pero para mapear el AOH como una presencia o ausencia binaria, fue necesario aplicar un umbral de asociación. Este umbral puede ser elegido por el usuario de acuerdo con el balance requerido entre los errores de omisión y comisión. Algunos hábitats (p. ej.: bosques y desiertos) fueron asignados a las categorías de cobertura de terreno con más confianza que otros (p. ej.: humedales y artificiales). El modelo de conversión orientado por los datos y el conocimiento de los expertos tuvieron un desempeño igual de eficiente, pero el modelo proporcionó una mayor estandarización, objetividad y repetitividad. Además, nuestra estrategia permitió una mayor flexibilidad en el uso de los resultados y de la incertidumbre para ser cuantificados. Nuestro modelo puede modificarse para análisis regionales y para diferentes grupos taxonómicos.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Aves , Bosques , Mamíferos , Vertebrados
10.
Sensors (Basel) ; 22(14)2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35891046

RESUMEN

Soil moisture (SM) is an important parameter in land surface processes and the global water cycle. Remote sensing technologies are widely used to produce global-scale SM products (e.g., European Space Agency's Climate Change Initiative (ESA CCI)). However, the current spatial resolutions of such products are low (e.g., >3 km). In recent years, using auxiliary data to downscale the spatial resolutions of SM products has been a hot research topic in the remote sensing research area. A new method, which spatially downscalesan SM product to generate a daily SM dataset at a 16 m spatial resolution based on a spatiotemporal fusion model (STFM) and modified perpendicular drought index (MPDI), was proposed in this paper. (1) First, a daily surface reflectance dataset with a 16 m spatial resolution was produced based on an STFM. (2) Then, a spatial scale conversion factor (SSCF) dataset was obtained by an MPDI dataset, which was calculated based on the dataset fused in the first step. (3) Third, a downscaled daily SM product with a 16 m spatial resolution was generated by combining the SSCF dataset and the original SM product. Five cities in southern Hebei Province were selected as study areas. Two 16 m GF6 images and nine 500 m MOD09GA images were used as auxiliary data to downscale a timeseries 25 km CCI SM dataset for nine dates from May to June 2019. A total of 151 in situ SM observations collected on 1 May, 21 May, 1 June, and 11 June were used for verification. The results indicated that the downscaled SM data with a 16 m spatial resolution had higher correlation coefficients and lower RMSE values compared with the original CCI SM data. The correlation coefficients between the downscaled SM data and in situ data ranged from 0.45 to 0.67 versus 0.33 to 0.54 for the original CCI SM data; the RMSE values ranged from 0.023 to 0.031 cm3/cm3 versus 0.027 to 0.032 cm3/cm3 for the original CCI SM data. The findings described in this paper can ensure effective farmland management and other practical production applications.


Asunto(s)
Sequías , Suelo , Cambio Climático , Monitoreo del Ambiente/métodos , Tecnología de Sensores Remotos/métodos
11.
Int J Mol Sci ; 23(5)2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35269626

RESUMEN

In spite of their value as genetically encodable reporters for imaging in living systems, fluorescent proteins have been used sporadically for stimulated emission depletion (STED) super-resolution imaging, owing to their moderate photophysical resistance, which does not enable reaching resolutions as high as for synthetic dyes. By a rational approach combining steady-state and ultrafast spectroscopy with gated STED imaging in living and fixed cells, we here demonstrate that F99S/M153T/V163A GFP (c3GFP) represents an efficient genetic reporter for STED, on account of no excited state absorption at depletion wavelengths <600 nm and a long emission lifetime. This makes c3GFP a valuable alternative to more common, but less photostable, EGFP and YFP/Citrine mutants for STED imaging studies targeting the green-yellow region of the optical spectrum.


Asunto(s)
Colorantes Fluorescentes , Colorantes Fluorescentes/química , Proteínas Fluorescentes Verdes/genética , Microscopía Fluorescente/métodos
12.
Environ Manage ; 70(5): 710-729, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36100759

RESUMEN

Proactive Conservation is a paradigm of natural resource management in the United States that encourages voluntary, collaborative efforts to restore species before they need to be protected through government regulations. This paradigm is widely used to conserve at-risk species today, and when used in conjunction with the Policy for Evaluation of Conservation Efforts (PECE), it allows for successful conservation actions to preclude listing of species under the Endangered Species Act (ESA). Despite the popularity of this paradigm, and recent flagship examples of its use (e.g., greater sage grouse, Centrocercus urophasianus), critical assessments of the outcomes of Proactive Conservation are lacking from the standpoint of species status and recovery metrics. Here, we provide such an evaluation, using the New England cottontail (Sylvilagus transitionalis), heralded as a success of Proactive Conservation efforts in the northeastern United States, as a case study. We review the history and current status of the species, based on the state of the science, in the context of the Conservation Initiative, and the 2015 PECE decision not to the list the species under the ESA. In addition to the impacts of the PECE decision on the New England cottontail conservation specifically, our review also evaluates the benefits and limits of the Proactive Conservation paradigm more broadly, and we make recommendations for its role in relation to ESA implementation for the future of at-risk species management. We find that the status and assurances for recovery under the PECE policy, presented at the time of the New England cottontail listing decision, were overly optimistic, and the status of the species has worsened in subsequent years. We suggest that use of PECE to avoid listing may occur because of the perception of the ESA as a punitive law and a misconception that it is a failure, although very few listed species have gone extinct. Redefining recovery to decouple it from delisting and instead link it to probability of persistence under recommended conservation measures would remove some of the stigma of listing, and it would strengthen the role of Species Status Assessments in endangered species conservation.


Asunto(s)
Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Animales , New England , Probabilidad , Estados Unidos
13.
Exp Astron (Dordr) ; 54(2-3): 641-676, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36915625

RESUMEN

The objective of this White Paper, submitted to ESA's Voyage 2050 call, is to get a more holistic knowledge of the dynamics of the Martian plasma system, from its surface up to the undisturbed solar wind outside of the induced magnetosphere. This can only be achieved with coordinated multi-point observations with high temporal resolution as they have the scientific potential to track the whole dynamics of the system (from small to large scales), and they constitute the next generation of the exploration of Mars analogous to what happened at Earth a few decades ago. This White Paper discusses the key science questions that are still open at Mars and how they could be addressed with coordinated multipoint missions. The main science questions are: (i) How does solar wind driving impact the dynamics of the magnetosphere and ionosphere? (ii) What is the structure and nature of the tail of Mars' magnetosphere at all scales? (iii) How does the lower atmosphere couple to the upper atmosphere? (iv) Why should we have a permanent in-situ Space Weather monitor at Mars? Each science question is devoted to a specific plasma region, and includes several specific scientific objectives to study in the coming decades. In addition, two mission concepts are also proposed based on coordinated multi-point science from a constellation of orbiting and ground-based platforms, which focus on understanding and solving the current science gaps.

14.
Vnitr Lek ; 68(7): 438-443, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36402568

RESUMEN

Anaemia is a very common complication of chronic kidney disease (CKD) and renal failure. The view of the treatment of anaemia has changed considerably since the introduction of ESAs (erythropoiesis-stimulating agents) into clinical practice, and the safety of this treatment is now prioritised over complete normalisation of haemoglobin (Hb) values. Iron administration is the mainstay of treatment in this group of patients, with intravenous administration proving to be both more effective and safer in both predialysis and dialysis patients. In addition to the long-used ESAs, a number of new agents developed to favourably influence erythropoiesis have recently been tested for the correction of anaemia. Among those with the greatest potential are the HIF-stabilizers (roxadustat, molidustat, vadadustat and daprodustat), which act through stimulation of erythropoiesis genes and thus represent a novel mechanism of action in the treatment of anaemia. In phase 3 clinical trials, these agents have shown the same efficacy in increasing Hb levels as ESAs, but much emphasis has recently been placed on their safety profile. They are orally administered agents and some of them are already approved and used in clinical practice. The first of these, roxadustat, is currently reimbursed also in the Czech Republic. Other molecules affecting anaemia, such as sotatercept, have also been confirmed to be effective in phase 1 and 2 clinical trials and are awaiting results from larger randomised trials.


Asunto(s)
Anemia , Eritropoyetina , Hematínicos , Inhibidores de Prolil-Hidroxilasa , Insuficiencia Renal Crónica , Humanos , Inhibidores de Prolil-Hidroxilasa/uso terapéutico , Insuficiencia Renal Crónica/complicaciones , Anemia/tratamiento farmacológico , Anemia/etiología , Hematínicos/uso terapéutico
15.
J Biol Chem ; 295(46): 15482-15497, 2020 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-32878983

RESUMEN

In Saccharomyces cerevisiae, the Pif1 helicase functions in both nuclear and mitochondrial DNA replication and repair processes, preferentially unwinding RNA:DNA hybrids and resolving G-quadruplex structures. We sought to determine how the various activities of Pif1 are regulated in vivo Here, we report lysine acetylation of nuclear Pif1 and demonstrate that it influences both Pif1's cellular roles and core biochemical activities. Using Pif1 overexpression toxicity assays, we determined that the acetyltransferase NuA4 and deacetylase Rpd3 are primarily responsible for the dynamic acetylation of nuclear Pif1. MS analysis revealed that Pif1 was modified in several domains throughout the protein's sequence on the N terminus (Lys-118 and Lys-129), helicase domain (Lys-525, Lys-639, and Lys-725), and C terminus (Lys-800). Acetylation of Pif1 exacerbated its overexpression toxicity phenotype, which was alleviated upon deletion of its N terminus. Biochemical assays demonstrated that acetylation of Pif1 stimulated its helicase, ATPase, and DNA-binding activities, whereas maintaining its substrate preferences. Limited proteolysis assays indicate that acetylation of Pif1 induces a conformational change that may account for its altered enzymatic properties. We propose that acetylation is involved in regulating of Pif1 activities, influencing a multitude of DNA transactions vital to the maintenance of genome integrity.


Asunto(s)
Núcleo Celular/metabolismo , ADN Helicasas/metabolismo , Lisina/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Acetilación , ADN Helicasas/química , ADN Helicasas/genética , ADN de Hongos/metabolismo , Histona Acetiltransferasas/química , Histona Acetiltransferasas/metabolismo , Histona Desacetilasas/metabolismo , Mutagénesis Sitio-Dirigida , Dominios Proteicos , ARN de Hongos/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Especificidad por Sustrato , Espectrometría de Masas en Tándem
16.
Curr Genet ; 67(1): 85-92, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33079209

RESUMEN

PIF1 family helicases are evolutionarily conserved among prokaryotes and eukaryotes. These enzymes function to support genome integrity by participating in multiple DNA transactions that can be broadly grouped into DNA replication, DNA repair, and telomere maintenance roles. However, the levels of PIF1 activity in cells must be carefully controlled, as Pif1 over-expression in Saccharomyces cerevisiae is toxic, and knockdown or over-expression of human PIF1 (hPIF1) supports cancer cell growth. This suggests that PIF1 family helicases must be subject to tight regulation in vivo to direct their activities to where and when they are needed, as well as to maintain those activities at proper homeostatic levels. Previous work shows that C-terminal phosphorylation of S. cerevisiae Pif1 regulates its telomere maintenance activity, and we recently identified that Pif1 is also regulated by lysine acetylation. The over-expression toxicity of Pif1 was exacerbated in cells lacking the Rpd3 lysine deacetylase, but mutation of the NuA4 lysine acetyltransferase subunit Esa1 ameliorated this toxicity. Using recombinant proteins, we found that acetylation stimulated the DNA binding affinity, ATPase activity, and DNA unwinding activities of Pif1. All three domains of the helicase were targets of acetylation in vitro, and multiple lines of evidence suggest that acetylation drives a conformational change in the N-terminal domain of Pif1 that impacts this stimulation. It is currently unclear what triggers lysine acetylation of Pif1 and how this modification impacts the many in vivo functions of the helicase, but future work promises to shed light on how this protein is tightly regulated within the cell.


Asunto(s)
ADN Helicasas/genética , Inestabilidad Genómica/genética , Histona Acetiltransferasas/genética , Proteínas de Saccharomyces cerevisiae/genética , Acetilación , Reparación del ADN/genética , Replicación del ADN/genética , Regulación Fúngica de la Expresión Génica/genética , Histona Desacetilasas/genética , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Saccharomyces cerevisiae/genética , Telómero/genética , Homeostasis del Telómero/genética
17.
BMC Cancer ; 21(1): 385, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33836674

RESUMEN

BACKGROUND: Herein, we investigate the relationship between pancreatic stem cell markers (PCSC markers), CD44, and epithelial-specific antigen (ESA), tumor stroma, and the impact on recurrence outcomes in pancreatic ductal adenocarcinoma (PDAC) patients. METHODS: PDAC patients who underwent surgical resection between 01/2012-06/2014 were identified. CD44 and ESA expression was assessed by immunohistochemistry. Stroma was classified as loose, moderate, and dense based on fibroblast content. Overall survival (OS) and relapse-free survival (RFS) were estimated using the Kaplan-Meier method and compared between subgroups by log-rank test. The association between PCSC markers and stroma type was assessed by Fisher's exact test. RESULTS: N = 93 PDAC patients were identified. The number of PDAC patients with dense, moderate density, and loose stroma was 11 (12%), 51 (54%), and 31 (33%) respectively. PDAC with CD44+/ESA- had highest rate of loose stroma (63%) followed by PDAC CD44+/ESA+ (50%), PDAC CD44-/ESA+ (35%), CD44-/ESA- (9%) (p = 0.0033). Conversely, lack of CD44 and ESA expression was associated with the highest rate of moderate and dense stroma (91% p = 0.0033). No local recurrence was observed in patients with dense stroma and 9 had distant recurrence. The highest rate of cumulative local recurrence was observed in patients with loose stroma. No statistically significant difference in RFS and OS was observed among subgroups (P = 0.089). CONCLUSIONS: These data indicate PCSCs may have an important role in stroma differentiation in PDAC. Our results further suggest that tumor stroma may influence the recurrence pattern in PDAC patients.


Asunto(s)
Fibroblastos Asociados al Cáncer/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Células Madre Neoplásicas/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Células del Estroma/metabolismo , Biomarcadores , Fibroblastos Asociados al Cáncer/patología , Carcinoma Ductal Pancreático/mortalidad , Carcinoma Ductal Pancreático/terapia , Terapia Combinada , Femenino , Humanos , Inmunohistoquímica , Masculino , Clasificación del Tumor , Metástasis de la Neoplasia , Estadificación de Neoplasias , Células Madre Neoplásicas/patología , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/terapia , Pronóstico , Recurrencia , Células del Estroma/patología , Resultado del Tratamiento , Microambiente Tumoral
18.
Nephrol Dial Transplant ; 36(2): 267-274, 2021 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-32829405

RESUMEN

BACKGROUND: Despite the widespread use of erythropoiesis-stimulating agents (ESAs) to treat anaemia, the risk of adverse outcomes associated with the use of different types of ESAs in non-dialysis chronic kidney disease (CKD) is poorly investigated. METHODS: From a pooled cohort of four observational studies, we selected CKD patients receiving short-acting (epoetin α/ß; n = 299) or long-acting ESAs (darbepoetin and methoxy polyethylene glycol-epoetin ß; n = 403). The primary composite endpoint was end-stage kidney disease (ESKD; dialysis or transplantation) or all-cause death. Multivariable Cox models were used to estimate the relative risk of the primary endpoint between short- and long-acting ESA users. RESULTS: During follow-up [median 3.6 years (interquartile range 2.1-6.3)], the primary endpoint was registered in 401 patients [166 (72%) in the short-acting ESA group and 235 (58%) in the long-acting ESA group]. In the highest tertile of short-acting ESA dose, the adjusted risk of primary endpoint was 2-fold higher {hazard ratio [HR] 2.07 [95% confidence interval (CI) 1.37-3.12]} than in the lowest tertile, whereas it did not change across tertiles of dose for long-acting ESA patients. Furthermore, the comparison of ESA type in each tertile of ESA dose disclosed a significant difference only in the highest tertile, where the risk of the primary endpoint was significantly higher in patients receiving short-acting ESAs [HR 1.56 (95% CI 1.09-2.24); P = 0.016]. Results were confirmed when ESA dose was analysed as continuous variable with a significant difference in the primary endpoint between short- and long-acting ESAs for doses >105 IU/kg/week. CONCLUSIONS: Among non-dialysis CKD patients, the use of a short-acting ESA may be associated with an increased risk of ESKD or death versus long-acting ESAs when higher ESA doses are prescribed.


Asunto(s)
Anemia/tratamiento farmacológico , Hematínicos/efectos adversos , Hematínicos/clasificación , Fallo Renal Crónico/mortalidad , Insuficiencia Renal Crónica/complicaciones , Anciano , Anemia/etiología , Anemia/patología , Causas de Muerte , Estudios de Cohortes , Eritropoyesis/efectos de los fármacos , Femenino , Humanos , Fallo Renal Crónico/inducido químicamente , Fallo Renal Crónico/patología , Masculino , Estudios Observacionales como Asunto , Diálisis Renal , Tasa de Supervivencia
19.
Pediatr Nephrol ; 36(2): 473-476, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33156411

RESUMEN

BACKGROUND: Vitamin B6 is a rate-limiting coenzyme that plays an important role in the biosynthesis of heme and the incorporation of iron into protoporphyrin. Its deficiency is often seen in chronic kidney disease (CKD), particularly those requiring dialysis and following administration of erythropoietin-stimulating agent (ESA). CASE- DIAGNOSIS/TREATMENT: A 16-year-old African-American male with stage 5 CKD on chronic hemodialysis experienced a decrease in hemoglobin over a 3-month period from 11 to 6.5 g/dl while receiving ESA, resulting in multiple blood transfusions. His transferrin saturation was 41%, ferritin level 706 [80-388] ng/mL, mean corpuscular volume (MCV) 87 [78-98] µm3, corrected reticulocytes count 2.3% [0.2-1.8%], and vitamin B6 1.2 [5.3-46.7] µg/L. Bone marrow biopsy was normocellular (65%) with erythroid hyperplasia and rare dyserythropoiesis. Prussian blue staining showed increased iron storage. Supplemental vitamin B6 (100 mg daily) was initiated at hemoglobin 7.3 g/dL with correction of anemia. Eighteen months later, his hemoglobin is 11.7 g/dL, transferrin saturation 45%, with no additional blood transfusions. CONCLUSIONS: Vitamin B6 deficiency anemia should be considered in any pediatric patient on hemodialysis who does not respond to standard ESA and iron therapy.


Asunto(s)
Anemia Ferropénica , Anemia , Eritropoyetina , Hematínicos , Fallo Renal Crónico , Insuficiencia Renal Crónica , Adolescente , Anemia/tratamiento farmacológico , Anemia/etiología , Niño , Epoetina alfa , Hematínicos/uso terapéutico , Hemoglobinas/metabolismo , Humanos , Hierro , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Masculino , Diálisis Renal/efectos adversos , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/terapia , Transferrinas , Vitamina B 6 , Vitaminas
20.
Clin Exp Nephrol ; 25(5): 456-466, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33411115

RESUMEN

BACKGROUND: There is no evidence regarding appropriate target hemoglobin levels in chronic kidney disease (CKD) patients with an erythropoiesis-stimulating agent (ESA)-hyporesponsiveness. Therefore, we conducted a randomized controlled study in non-dialysis dependent CKD (NDD-CKD) patients with ESA-hyporesponsiveness, comparing results of intensive versus conservative treatment to maintain hemoglobin levels. METHODS: This was a multicenter, open-label, randomized, parallel-group study conducted at 89 institutions. Among NDD-CKD patients, those with ESA-hyporesponsive renal anemia were randomly assigned to an intensive treatment group, to which epoetin beta pegol was administered with target hemoglobin level of 11 g/dL or higher, or conservative treatment group, in which the hemoglobin levels at enrollment (within ± 1 g/dL) were maintained. The primary endpoint was the time to the first kidney composite event defined as (1) transition to renal replacement therapy (dialysis or renal transplantation); (2) reduction of estimated glomerular filtration rate (eGFR) to less than 6.0 mL/min/1.73 m2; or (3) reduction of eGFR by 30% or more. Secondary endpoints were kidney function (change rate in eGFR), cardiovascular (CV) events, and safety. RESULTS: Between August 2012 and December 2015, 385 patients were registered, and 362 patients who met the eligibility criteria were enrolled. There was no significant difference in kidney survival or in CV events between the two groups. However, the incidences of the 3 types of kidney composite events tended to differ. CONCLUSIONS: In NDD-CKD patients with ESA-hyporesponsive renal anemia, the aggressive administration of ESA did not clearly extend kidney survival or result in a significant difference in the incidence of CV events.


Asunto(s)
Anemia/tratamiento farmacológico , Eritropoyetina/administración & dosificación , Hematínicos/administración & dosificación , Hemoglobinas/metabolismo , Polietilenglicoles/administración & dosificación , Insuficiencia Renal Crónica/fisiopatología , Anciano , Anciano de 80 o más Años , Anemia/sangre , Anemia/etiología , Enfermedades Cardiovasculares/etiología , Resistencia a Medicamentos , Eritropoyetina/efectos adversos , Femenino , Tasa de Filtración Glomerular , Hematínicos/efectos adversos , Humanos , Trasplante de Riñón , Masculino , Persona de Mediana Edad , Polietilenglicoles/efectos adversos , Pronóstico , Diálisis Renal , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/terapia
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