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1.
Sensors (Basel) ; 24(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38732996

RESUMEN

X-ray nanotomography is a powerful tool for the characterization of nanoscale materials and structures, but it is difficult to implement due to the competing requirements of X-ray flux and spot size. Due to this constraint, state-of-the-art nanotomography is predominantly performed at large synchrotron facilities. We present a laboratory-scale nanotomography instrument that achieves nanoscale spatial resolution while addressing the limitations of conventional tomography tools. The instrument combines the electron beam of a scanning electron microscope (SEM) with the precise, broadband X-ray detection of a superconducting transition-edge sensor (TES) microcalorimeter. The electron beam generates a highly focused X-ray spot on a metal target held micrometers away from the sample of interest, while the TES spectrometer isolates target photons with a high signal-to-noise ratio. This combination of a focused X-ray spot, energy-resolved X-ray detection, and unique system geometry enables nanoscale, element-specific X-ray imaging in a compact footprint. The proof of concept for this approach to X-ray nanotomography is demonstrated by imaging 160 nm features in three dimensions in six layers of a Cu-SiO2 integrated circuit, and a path toward finer resolution and enhanced imaging capabilities is discussed.

2.
Breast Cancer Res Treat ; 168(2): 311-325, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29236234

RESUMEN

PURPOSE: The molecular mechanism of breast and/or ovarian cancer susceptibility remains unclear in the majority of patients. While germline mutations in the regulatory non-coding regions of BRCA1 and BRCA2 genes have been described, screening has generally been limited to coding regions. The aim of this study was to evaluate the contribution of BRCA1/2 non-coding variants. METHODS: Four BRCA1/2 non-coding regions were screened using high-resolution melting analysis/Sanger sequencing or next-generation sequencing on DNA extracted from index cases with breast and ovarian cancer predisposition (3926 for BRCA1 and 3910 for BRCA2). The impact of a set of variants on BRCA1/2 gene regulation was evaluated by site-directed mutagenesis, transfection, followed by Luciferase gene reporter assay. RESULTS: We identified a total of 117 variants and tested twelve BRCA1 and 8 BRCA2 variants mapping to promoter and intronic regions. We highlighted two neighboring BRCA1 promoter variants (c.-130del; c.-125C > T) and one BRCA2 promoter variants (c.-296C > T) inhibiting significantly the promoter activity. In the functional assays, a regulating region within the intron 12 was found with the same enhancing impact as within the intron 2. Furthermore, the variants c.81-3980A > G and c.4186-2022C > T suppress the positive effect of the introns 2 and 12, respectively, on the BRCA1 promoter activity. We also found some variants inducing the promoter activities. CONCLUSION: In this study, we highlighted some variants among many, modulating negatively the promoter activity of BRCA1 or 2 and thus having a potential impact on the risk of developing cancer. This selection makes it possible to conduct future validation studies on a limited number of variants.


Asunto(s)
Proteína BRCA1/genética , Proteína BRCA2/genética , Genes BRCA1 , Genes BRCA2 , Síndrome de Cáncer de Mama y Ovario Hereditario/genética , Adulto , Anciano , Estudios de Cohortes , Biología Computacional , Femenino , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Intrones/genética , Persona de Mediana Edad , Linaje , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas/genética , Regiones no Traducidas/genética
3.
Int J Obes (Lond) ; 40(9): 1392-6, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27113642

RESUMEN

BACKGROUND/OBJECTIVES: Regular self-weighing has been associated with weight loss and maintenance in adults enrolled in a behavioral weight loss intervention; however, few studies have examined the patterns of adherence to a self-weighing protocol. The study aims were to (1) identify patterns of self-weighing behavior; and (2) examine adherence to energy intake and step goals and weight change by self-weighing patterns. SUBJECTS/METHODS: This was a secondary analysis of self-monitoring and assessment weight data from a 12-month behavioral weight loss intervention study. Each participant was given a scale that was Wi-Fi-enabled and transmitted the date-stamped weight data to a central server. Group-based trajectory modeling was used to identify distinct classes of trajectories based on the number of days participants self-weighed over 51 weeks. RESULTS: The sample (N=148) was 90.5% female, 81.1% non-Hispanic white, with a mean (s.d.) age of 51.3 (10.1) years, had completed an average of 16.4 (2.8) years of education and had mean body mass index of 34.1 (4.6) kg m(-2). Three patterns of self-weighing were identified: high/consistent (n=111, 75.0% self-weighed over 6 days per week regularly); moderate/declined (n=24, 16.2% declined from 4-5 to 2 days per week gradually); and minimal/declined (n=13, 8.8% declined from 5-6 to 0 days per week after week 33). The high/consistent group achieved greater weight loss than either the moderate/declined and minimal/declined groups at 6 months (-10.19%±5.78%, -5.45%±4.73% and -2.00%±4.58%) and 12 months (-9.90%±8.16%, -5.62%±6.28% and 0.65%±3.58%), respectively (P<0.001). The high/consistent group had a greater mean number days per week of adherence to calorie intake goal or step goal but not higher than the moderate/declined group. CONCLUSIONS: This is the first study to reveal distinct temporal patterns of self-weighing behavior. The majority of participants were able to sustain a habit of daily self-weighing with regular self-weighing leading to weight loss and maintenance as well as adherence to energy intake and step goals.


Asunto(s)
Conductas Relacionadas con la Salud , Obesidad/psicología , Cooperación del Paciente/psicología , Autocuidado , Pérdida de Peso/fisiología , Programas de Reducción de Peso , Ingestión de Energía , Femenino , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Obesidad/prevención & control , Cooperación del Paciente/estadística & datos numéricos , Autocuidado/psicología , Estados Unidos
4.
Qual Life Res ; 25(5): 1103-12, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26563251

RESUMEN

While the use of PROs in research is well established, many challenges lie ahead as their use is extended to other applications. There is consensus that health outcome evaluations that include PROs along with clinician-reported outcomes and administrative data are necessary to inform clinical and policy decisions. The initiatives presented in this paper underline evolving recognition that PROs play a unique role in adding the patient perspective alongside clinical (e.g., blood pressure) and organizational (e.g., admission rates) indicators for evaluating the effects of new products, selecting treatments, evaluating quality of care, and monitoring the health of the population. In this paper, we first explore the use of PRO measures to support drug approval and labeling claims. We critically evaluate the evidence and challenges associated with using PRO measures to improve healthcare delivery at individual and population levels. We further discuss the challenges associated with selecting from the abundance of measures available, opportunities afforded by agreeing on common metrics for constructs of interest, and the importance of establishing an evidence base that supports integrating PRO measures across the healthcare system to improve outcomes. We conclude that the integration of PROs as a key end point within individual patient care, healthcare organization and program performance evaluations, and population surveillance will be essential for evaluating whether increased healthcare expenditure is translating into better health outcomes.


Asunto(s)
Evaluación del Resultado de la Atención al Paciente , Garantía de la Calidad de Atención de Salud , Mejoramiento de la Calidad , Atención a la Salud , Estado de Salud , Humanos , Evaluación de Programas y Proyectos de Salud , Calidad de Vida
5.
Lung ; 193(1): 71-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25381634

RESUMEN

INTRODUCTION: Despite advances in diagnosis and management, the outcomes for both lung cancer and idiopathic pulmonary fibrosis (IPF) are still unfavourable. The pathophysiology and outcomes for patients with concomitant lung cancer and IPF remains unclear. METHODOLOGY: A retrospective analysis was performed of all patients presenting with concomitant IPF and lung cancer to our centre over a 3-year period. Patients with connective tissue disease, asbestos exposure, sarcoidosis, previous thoracic radiation, radiological evidence of fibrosis but no histological confirmation of lung cancer, or the use of medications known to cause pulmonary fibrosis were excluded. We describe clinical, radiological and pathological characteristics of this group. We also report the response to standardized lung cancer therapy in this cohort. RESULTS: Of 637 lung cancer patients, 34 were identified with concomitant IPF (5.3 %) and all were smokers. 85 % had non-small cell lung cancer, 41 % were squamous cell cancers. The majority of tumours were located in the lower lobes, peripheral and present in an area of honeycombing. Despite the fact that approximately 2/3rds of the patients had localised or locally advanced lung cancer, the outcome of therapy for lung cancer was extremely poor regardless of tumour stage or severity of IPF. CONCLUSIONS: At our centre, 1/20 patients with lung cancer have concomitant IPF. The majority of these tumours are small in size, peripheral in location and squamous cell carcinoma; in an area of honey combing. The outcome for concomitant lung cancer and IPF regardless of stage or therapy is poor.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/complicaciones , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas/diagnóstico , Fibrosis Pulmonar Idiopática/complicaciones , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/diagnóstico , Pulmón/diagnóstico por imagen , Pulmón/patología , Anciano , Biopsia , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Femenino , Humanos , Fibrosis Pulmonar Idiopática/diagnóstico , Fibrosis Pulmonar Idiopática/mortalidad , Irlanda , Estimación de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Fumar/efectos adversos , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Carga Tumoral
6.
Radiologia ; 56(6): 533-40, 2014.
Artículo en Inglés, Español | MEDLINE | ID: mdl-23337695

RESUMEN

PURPOSE: To investigate whether increasing temporal resolution with higher parallel imaging (PI) reduction factors (RF) in both breath-hold and free breathing approaches, using a non-contrast T1-weighted 3D gradient echo (GRE) sequence and a 32-channel phased array coil, permits diagnostic image quality, with potential application in patients unable to cooperate with breath-hold requirements. MATERIALS AND METHODS: The 9 healthy subjects (5 females and 4 males; age range was 20-49, mean 36 yrs) were recruited. A 3D GRE MR imaging of the abdomen was performed on 1.5 T MR system using a 32-element phased-array torso coil with PI RFs of 2, 4 and 6, breath hold and free breathing. Two reviewers retrospectively qualitatively evaluated all sequences for image quality, extent of artifacts, including motion, truncation, aliasing, pixel graininess and signal heterogeneity. The results were compared using Wilcoxon signed rank and a Bonferroni adjustment was applied for multiple comparisons. RESULTS: Image quality and extent of artifacts were better with breath hold than with free breathing acquisitions. The rate of artifacts increased with higher RF. The best quality was acquired with breath hold sequence using RF=2. RF=4 had lower but diagnostic rates (P=.004). The severity of artifacts, mainly pixel graininess (P=.004), rendered sequences with RF=6 non-diagnostic. All sequences were non-diagnostic in free breathing acquisitions. CONCLUSION: Breath hold sequences with RF=2 had excellent quality and RF=4 had good quality and may be potentially used in partially cooperative patients. None of the sequences was considered diagnostic in free breathing acquisitions.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Respiración , Adulto , Contencion de la Respiración , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
7.
Br J Dermatol ; 168(3): 496-503, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23121233

RESUMEN

BACKGROUND: Epidermogenesis and epidermal wound healing are tightly regulated processes during which keratinocytes must migrate, proliferate and differentiate. Cell-to-cell adhesion is crucial to the initiation and regulation of these processes. CUB-domain-containing protein (CDCP)1 is a transmembrane glycoprotein that is differentially tyrosine phosphorylated during changes in cell adhesion and survival signalling, and is expressed by keratinocytes in native human skin, as well as in primary cultures. OBJECTIVES: To investigate the expression of CDCP1 during epidermogenesis and its role in keratinocyte migration. METHODS: We examined both human skin tissue and an in vitro three-dimensional human skin equivalent model to examine the expression of CDCP1 during epidermogenesis. To examine the role of CDCP1 in keratinocyte migration we used a function-blocking anti-CDCP1 antibody and a real-time Transwell™ cell migration assay. RESULTS: Immunohistochemical analysis indicated that in native human skin CDCP1 is expressed in the stratum basale and stratum spinosum. In contrast, during epidermogenesis in a three-dimensional human skin equivalent model, CDCP1 was expressed only in the stratum basale, with localization restricted to the cell-cell membrane. No expression was detected in basal keratinocytes that were in contact with the basement membrane. Furthermore, an anti-CDCP1 function-blocking antibody was shown to disrupt keratinocyte chemotactic migration in vitro. CONCLUSIONS: These findings delineate the expression of CDCP1 in human epidermal keratinocytes during epidermogenesis and demonstrate that CDCP1 is involved in keratinocyte migration.


Asunto(s)
Antígenos CD/metabolismo , Moléculas de Adhesión Celular/metabolismo , Movimiento Celular/fisiología , Células Epidérmicas , Queratinocitos/metabolismo , Proteínas de Neoplasias/metabolismo , Adulto , Antígenos CD/fisiología , Antígenos de Neoplasias , Adhesión Celular/fisiología , Moléculas de Adhesión Celular/fisiología , Diferenciación Celular/fisiología , Ensayos de Migración Celular/métodos , Proliferación Celular , Quimiotaxis/fisiología , Epidermis/metabolismo , Humanos , Inmunohistoquímica , Modelos Biológicos , Proteínas de Neoplasias/fisiología
8.
Artículo en Inglés | MEDLINE | ID: mdl-37003144

RESUMEN

BACKGROUND: Aspirin and eicosapentaenoic acid (EPA) have colorectal polyp prevention activity, alone and in combination. This study measured levels of plasma and rectal mucosal oxylipins in participants of the seAFOod 2 × 2 factorial, randomised, placebo-controlled trial, who received aspirin 300 mg daily and EPA 2000 mg free fatty acid, alone and in combination, for 12 months. METHODS: Resolvin (Rv) E1, 15-epi-lipoxin (LX) A4 and respective precursors 18-HEPE and 15-HETE (with chiral separation) were measured by ultra-high performance liquid chromatography-tandem mass spectrometry in plasma taken at baseline, 6 months and 12 months, as well as rectal mucosa obtained at trial exit colonoscopy at 12 months, in 401 trial participants. RESULTS: Despite detection of S- and R- enantiomers of 18-HEPE and 15-HETE in ng/ml concentrations, RvE1 or 15­epi-LXA4 were not detected above a limit of detection of 20 pg/ml in plasma or rectal mucosa, even in individuals randomised to both aspirin and EPA. We have confirmed in a large clinical trial cohort that prolonged (12 months) treatment with EPA is associated with increased plasma 18-HEPE concentrations (median [inter-quartile range] total 18-HEPE 0.51 [0.21-1.95] ng/ml at baseline versus 0.95 [0.46-4.06] ng/ml at 6 months [P<0.0001] in those randomised to EPA alone), which correlate strongly with respective rectal mucosal 18-HEPE levels (r = 0.82; P<0.001), but which do not predict polyp prevention efficacy by EPA or aspirin. CONCLUSION: Analysis of seAFOod trial plasma and rectal mucosal samples has not provided evidence of synthesis of the EPA-derived specialised pro-resolving mediator RvE1 or aspirin-trigged lipoxin 15­epi-LXA4. We cannot rule out degradation of individual oxylipins during sample collection and storage but readily measurable precursor oxylipins argues against widespread degradation.


Asunto(s)
Aspirina , Lipoxinas , Humanos , Aspirina/uso terapéutico , Ácido Eicosapentaenoico/uso terapéutico , Oxilipinas , Membrana Mucosa
9.
Int J Obes (Lond) ; 36(9): 1245-7, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22143617

RESUMEN

Human eating behaviour is motivated and shaped by a complex interaction of internal drives such as hunger, external influences such as environmental cues and the sensory properties of food itself. Thus, as is demonstrated by the example of sensory-specific satiety (SSS), hunger may be reduced but particular foods (for example, desserts) retain their attraction and their ability to prompt consumption. In considering consumption, and overconsumption, it is therefore important to understand the interaction between internal and external drives to eat. Using grip force as a measure of motivation, we examined this interaction using an SSS manipulation. Critically, we sought to determine whether food stimuli would exert their influence even when they were subliminally presented (and thus not accessible to consciousness), and whether this unconscious influence would be flexibly updated in response to changes in food reward value with satiety. Demonstrating that the SSS effect remains when external stimuli are not consciously perceived, our data highlight the importance of even the most subtle, fleeting and even subliminal external events in shaping our motivation towards food.


Asunto(s)
Ingestión de Alimentos/psicología , Conducta Alimentaria/psicología , Motivación , Estimulación Subliminal , Adulto , Ingestión de Energía , Femenino , Fuerza de la Mano , Humanos , Control Interno-Externo , Masculino , Saciedad , Encuestas y Cuestionarios
10.
Ir J Psychol Med ; 39(4): 335-339, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-31543078

RESUMEN

The psychedelic research renaissance is gaining traction. Preliminary clinical studies of the hallucinogenic fungi, psilocybin, with psychological support, have indicated improvements in mood, anxiety and quality of life. A seminal, open-label study demonstrated marked reductions in depression symptoms in participants with treatment-resistant depression (TRD). The associated neurobiological processes involve alterations in brain connectivity, together with altered amygdala and default mode network activity. At the cellular level, psychedelics promote synaptogenesis and neural plasticity. Prompted by the promising preliminary studies, a randomized, double-blind trial has recently been launched across Europe and North America to investigate the efficacy of psilocybin in TRD. One of these centres is based in Ireland - CHO Area 7 and Tallaght University Hospital. The outcome of this trial will determine whether psilocybin with psychological support will successfully translate into the psychiatric clinic for the benefit of patients.


Asunto(s)
Alucinógenos , Psiquiatría , Humanos , Ansiedad , Alucinógenos/uso terapéutico , Psilocibina/uso terapéutico , Calidad de Vida , Método Doble Ciego
11.
Trials ; 23(1): 848, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36195894

RESUMEN

BACKGROUND: Cardiotocography (CTG) is a screening test used to detect fetal hypoxia in labour. It has a high false positive rate resulting in many potentially unnecessary caesarean sections. Fetal blood sampling (FBS) is a second-line test of the acid-base status of the fetus. It is used to provide either reassurance that it is safe for labour to continue or objective evidence of compromise so that delivery can be expedited. Digital fetal scalp stimulation (dFSS) to elicit a fetal heart rate acceleration is an alternative less invasive second-line test of fetal wellbeing. This study aims to provide robust evidence on the role of these two second-line tests in assessing fetal wellbeing and potentially preventing operative delivery. METHODS: A multi-centre parallel group randomised controlled trial (RCT) is planned in four maternity centres in Ireland. The study aims to recruit 2500 nulliparous women with a term (≥37+0 weeks) singleton pregnancy who require a second-line test of fetal wellbeing in labour due to an abnormal CTG. Women will be allocated randomly to dFSS or FBS on a 1:1 ratio. The primary outcome is caesarean section. With 1250 women in each arm, the study will have 90% power to detect a difference of 5-6%, at a two-sided alpha significance level of 5%, assuming a caesarean section rate of at least 20% in the dFSS group. DISCUSSION: If the proposed study shows evidence that dFSS is a safe, reliable and effective alternative to FBS, this would have ground-breaking implications for labour management worldwide. It could potentially lead to a reduction in invasive procedures and emergency caesarean sections. TRIAL REGISTRATION: ClinicalTrials.gov NCT05306756. Registered on 31 March 2022. The trial commenced enrolment on 10 May 2022. Ethical committee approval has been granted by the Research Ethics Committee (REC) of each hospital: Dublin/CWIUH REC: 12.06.2019; Cork/UCC REC: 29.11.2019; Galway/NUIG REC: 06.09.2019; Limerick/UL REC: 30.09.2019.


Asunto(s)
Trabajo de Parto , Cuero Cabelludo , Cardiotocografía/métodos , Femenino , Sangre Fetal , Frecuencia Cardíaca Fetal/fisiología , Humanos , Embarazo
12.
Artículo en Inglés | MEDLINE | ID: mdl-35391998

RESUMEN

Purpose: To examine changes in physical activity (PA) during a behavioral weight-loss intervention and determine baseline factors associated with PA goal achievement. Methods: Overweight/obese community-dwelling adults with valid PA accelerometer data (N=116; mean age 51.7 years; 89% female; 83% non-Hispanic White) were recruited into a single-arm prospective cohort study examining the effects of a 12-month intervention that included 24 in-person group sessions, weight-loss, calorie, fat gram, and PA goals, self-monitoring, and feedback. Minutes of moderate-to-vigorous (MV) PA and steps were measured using a waist-worn accelerometer (ActiGraph GT3x) at baseline, 6 months, and 12 months. Achievement of the 150 minute/week MVPA goal was examined using total minutes and bout minutes (i.e., counting only PA occurring in bouts ≥10 minutes in length). Change in PA was analyzed using non-parametric tests for multiple comparisons. Associations of factors with meeting the PA goal were modeled using binary logistic regression. Results: At 6 months, there were increases from baseline in MVPA (median [p25, p75]: 5.3 [-0.9, 17.6] minutes/day) and steps (863 [-145, 2790] steps/day), both p<0.001. At 12 months, improvements were attenuated (MVPA: 2.4 [-2.0, 11.4] minutes/day, p=0.047; steps: 374[-570, 1804] p=0.14). At 6 months, 33.6% of individuals met the PA goal (using total or bout minutes). At 12 months, the percent meeting the goal using total MVPA [31%] differed from bout MVPA [22.4%]. Male gender (OR=4.14, p=0.027) and an autumn program start (versus winter; OR=3.39, p=0.011) were associated with greater odds of goal achievement at 6 months. Conclusions: The intervention increased PA goal achievement at 6 and 12 months with many making clinically meaningful improvements. Our results suggest female participants may require extra support toward improving PA levels.

13.
Langmuir ; 27(16): 10302-11, 2011 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-21721544

RESUMEN

The higher harmonic components available from large-amplitude Fourier-transformed alternating current (FT-ac) voltammetry enable the surface active state of a copper electrode in basic media to be probed in much more detail than possible with previously used dc methods. In particular, the absence of capacitance background current allows low-level Faradaic current contributions of fast electron-transfer processes to be detected; these are usually completely undetectable under conditions of dc cyclic voltammetry. Under high harmonic FT-ac voltammetric conditions, copper electrodes exhibit well-defined and reversible premonolayer oxidation responses at potentials within the double layer region in basic 1.0 M NaOH media. This process is attributed to oxidation of copper adatoms (Cu*) of low bulk metal lattice coordination numbers to surface-bonded, reactive hydrated oxide species. Of further interest is the observation that cathodic polarization in 1.0 M NaOH significantly enhances the current detected in each of the fundamental to sixth FT-ac harmonic components in the Cu*/Cu hydrous oxide electron-transfer process which enables the underlying electron transfer processes in the higher harmonics to be studied under conditions where the dc capacitance response is suppressed; the results support the incipient hydrous oxide adatom mediator (IHOAM) model of electrocatalysis. The underlying quasi-reversible interfacial Cu*/Cu hydrous oxide process present under these conditions is shown to mediate the reduction of nitrate at a copper electrode, while the mediator for the hydrazine oxidation reaction appears to involve a different mediator or active state redox couple. Use of FT-ac voltammetry offers prospects for new insights into the nature of active sites and electrocatalysis at the electrode/solution interface of Group 11 metals in aqueous media.

14.
Water Res ; 188: 116496, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33059158

RESUMEN

Verocytotoxin-producing E. coli (VTEC) are important agents of diarrhoeal disease in humans globally. As a noted waterborne disease, emphasis has been given to the study VTEC in surface waters, readily susceptible to microbial contamination. Conversely, the status of VTEC in potable groundwater sources, generally regarded as a "safe" drinking-water supply remains largely understudied. As such, this investigation presents the first scoping review seeking to determine the global prevalence of VTEC in groundwater supply sources intended for human consumption. Twenty-three peer-reviewed studies were identified and included for data extraction. Groundwater sample and supply detection rates (estimated 0.6 and 1.3%, respectively) indicate VTEC is infrequently present in domestic groundwater sources. However, where generic (fecal indicator) E. coli are present, the VTEC to E. coli ratio was found to be 9.9%, representing a latent health concern for groundwater consumers. Geographically, extracted data indicates higher VTEC detection rates in urban (5.4%) and peri­urban (4.9%) environments than in rural areas (0.9%); however, this finding is confounded by the predominance of research studies in lower income regions. Climate trends indicate local environments classified as 'temperate' (14/554; 2.5%) and 'cold' (8/392; 2%) accounted for a majority of supply sources with VTEC present, with similar detection rates encountered among supplies sampled during periods typically characterized by 'high' precipitation (15/649; 2.3%). Proposed prevalence figures may find application in preventive risk-based catchment and groundwater quality management including development of Quantitative Microbial Risk Assessments (QMRA). Notwithstanding, to an extent, a large geographical disparity in available investigations, lack of standardized reporting, and bias in source selection, restrict the transferability of research findings. Overall, the mechanisms responsible for VTEC transport and ingress into groundwater supplies remain ambiguous, representing a critical knowledge gap, and denoting a distinctive lack of integration between hydrogeological and public health research. Key recommendations and guidelines are provided for prospective studies directed at increasingly integrative and multi-disciplinary research.


Asunto(s)
Agua Subterránea , Escherichia coli Shiga-Toxigénica , Enfermedades Transmitidas por el Agua , Humanos , Estudios Prospectivos , Abastecimiento de Agua
15.
Ir J Psychol Med ; 38(2): 93-98, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32811575

RESUMEN

The medium- to long-term consequences of COVID-19 are not yet known, though an increase in mental health problems are predicted. Multidisciplinary strategies across socio-economic and psychological levels may be needed to mitigate the mental health burden of COVID-19. Preliminary evidence from the rapidly progressing field of psychedelic science shows that psilocybin therapy offers a promising transdiagnostic treatment strategy for a range of disorders with restricted and maladaptive habitual patterns of cognition and behaviour, notably depression, addiction and obsessive compulsive disorder. The COMPASS Pathways (COMPASS) phase 2b double-blind trial of psilocybin therapy in antidepressant-free, treatment-resistant depression (TRD) is underway to determine the safety, efficacy and optimal dose of psilocybin. Results from the Imperial College London Psilodep-RCT comparing the efficacy and mechanisms of action of psilocybin therapy to the selective serotonin reuptake inhibitor (SSRI) escitalopram will soon be published. However, the efficacy and safety of psilocybin therapy in conjunction with SSRIs in TRD is not yet known. An additional COMPASS study, with a centre in Dublin, will begin to address this question, with potential implications for the future delivery of psilocybin therapy. While at a relatively early stage of clinical development, and notwithstanding the immense challenges of COVID-19, psilocybin therapy has the potential to play an important therapeutic role for various psychiatric disorders in post-COVID-19 clinical psychiatry.


Asunto(s)
COVID-19 , Alucinógenos , Psiquiatría , Alucinógenos/uso terapéutico , Humanos , Psilocibina/uso terapéutico , SARS-CoV-2
16.
Scand J Med Sci Sports ; 20 Suppl 2: 48-58, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20840562

RESUMEN

Availability of carbohydrate as a substrate for the muscle and central nervous system is critical for the performance of both intermittent high-intensity work and prolonged aerobic exercise. Therefore, strategies that promote carbohydrate availability, such as ingesting carbohydrate before, during and after exercise, are critical for the performance of many sports and a key component of current sports nutrition guidelines. Guidelines for daily carbohydrate intakes have evolved from the "one size fits all" recommendation for a high-carbohydrate diets to an individualized approach to fuel needs based on the athlete's body size and exercise program. More recently, it has been suggested that athletes should train with low carbohydrate stores but restore fuel availability for competition ("train low, compete high"), based on observations that the intracellular signaling pathways underpinning adaptations to training are enhanced when exercise is undertaken with low glycogen stores. The present literature is limited to studies of "twice a day" training (low glycogen for the second session) or withholding carbohydrate intake during training sessions. Despite increasing the muscle adaptive response and reducing the reliance on carbohydrate utilization during exercise, there is no clear evidence that these strategies enhance exercise performance. Further studies on dietary periodization strategies, especially those mimicking real-life athletic practices, are needed.


Asunto(s)
Carbohidratos de la Dieta/metabolismo , Tolerancia al Ejercicio/fisiología , Estado Nutricional , Medicina Deportiva , Deportes/fisiología , Conducta Competitiva , Dieta , Humanos , Consumo de Oxígeno/fisiología , Guías de Práctica Clínica como Asunto , Análisis y Desempeño de Tareas , Factores de Tiempo
17.
Water Res ; 176: 115726, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32247994

RESUMEN

Cryptosporidiosis is one of the leading causes of diarrhoeal illness and mortality induced by protozoan pathogens worldwide. As a largely waterborne disease, emphasis has been given to the study of Cryptosporidium spp. in surface waters, readily susceptible to pathogenic contamination. Conversely, the status of Cryptosporidium in potable groundwater sources, generally regarded as a pristine and "safe" drinking-water supply owing to (sub)-soil protection, remains largely unknown. As such, this investigation presents the first literature review aimed to ascertain the global prevalence of Cryptosporidium in groundwater supply sources intended for human consumption. Thirty-seven peer-reviewed studies were identified and included in the review. Groundwater sample and supply detection rates (estimated 10-20%) indicate Cryptosporidium is frequently present in domestic groundwater sources, representing a latent health concern for groundwater consumers. Specifically, sample (10.4%) and source (19.1%) detection rates deriving from comprehensive "temporal" investigations are put forward as representative of a contamination 'baseline' for Cryptosporidium in 'domestic' groundwater supplies. Proposed 'baseline' prevalence figures are largely applicable in preventive risk-based catchment and groundwater quality management including the formulation of Quantitative Microbial Risk Assessment (QMRA). Notwithstanding, a large geographical disparity in available investigations and lack of standardized reporting restrict the transferability of research findings. Overall, the mechanisms responsible for Cryptosporidium transport and ingress into groundwater supplies remain ambiguous, representing a critical knowledge gap, and denoting a distinctive lack of integration between groundwater and public-health sub-disciplines among investigations. Key recommendations and guidelines are provided for prospective studies directed at more integrative and multi-disciplinary research.


Asunto(s)
Criptosporidiosis , Cryptosporidium , Agua Subterránea , Animales , Humanos , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Abastecimiento de Agua
19.
Ann Rheum Dis ; 68(12): 1894-7, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19155233

RESUMEN

OBJECTIVE: To assess the safety of biological disease-modifying antirheumatic drugs (DMARD) in rheumatoid arthritis (RA) patients following rituximab. METHODS: RA patients who participated in an international rituximab clinical trial programme were included. Patients who had received one or more rituximab courses and entered safety follow-up (SFU) were permitted additional biological DMARD. Serious infection events (SIE) were collected. RESULTS: Of 185 of 2578 patients who entered SFU and received another biological DMARD, 88.6% had peripheral B-cell depletion at the time of initiation of another biological agent. Thirteen SIE (6.99 events/100 patient-years) occurred following rituximab but before another biological DMARD and 10 SIE (5.49 events/100 patient-years) occurred following another biological DMARD. SIE were of typical type and severity for RA patients. 153 had received one or more tumour necrosis factor inhibitor(s). No fatal or opportunistic infections occurred. CONCLUSIONS: In this analysis, treatment with biological DMARD after rituximab was not associated with an increased serious infection rate. Sample size with limited follow-up restricts definitive conclusions.


Asunto(s)
Anticuerpos Monoclonales/efectos adversos , Antirreumáticos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Inmunosupresores/efectos adversos , Adulto , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales de Origen Murino , Antirreumáticos/uso terapéutico , Artritis Reumatoide/inmunología , Subgrupos de Linfocitos B/inmunología , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Huésped Inmunocomprometido , Inmunosupresores/uso terapéutico , Depleción Linfocítica/efectos adversos , Masculino , Persona de Mediana Edad , Infecciones Oportunistas/inducido químicamente , Infecciones Oportunistas/inmunología , Rituximab , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
20.
Science ; 364(6441)2019 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-31097641

RESUMEN

The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU69, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU69 is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU69's origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.

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