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1.
Phys Rev Lett ; 131(2): 021802, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37505961

RESUMEN

This Letter reports one of the most precise measurements to date of the antineutrino spectrum from a purely ^{235}U-fueled reactor, made with the final dataset from the PROSPECT-I detector at the High Flux Isotope Reactor. By extracting information from previously unused detector segments, this analysis effectively doubles the statistics of the previous PROSPECT measurement. The reconstructed energy spectrum is unfolded into antineutrino energy and compared with both the Huber-Mueller model and a spectrum from a commercial reactor burning multiple fuel isotopes. A local excess over the model is observed in the 5-7 MeV energy region. Comparison of the PROSPECT results with those from commercial reactors provides new constraints on the origin of this excess, disfavoring at 2.0 and 3.7 standard deviations the hypotheses that antineutrinos from ^{235}U are solely responsible and noncontributors to the excess observed at commercial reactors, respectively.

2.
Basic Res Cardiol ; 117(1): 39, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35970954

RESUMEN

The Hatter Cardiovascular Institute biennial workshop, originally scheduled for April 2020 but postponed for 2 years due to the Covid pandemic, was organised to debate and discuss the future of Remote Ischaemic Conditioning (RIC). This evolved from the large multicentre CONDI-2-ERIC-PPCI outcome study which demonstrated no additional benefit when using RIC in the setting of ST-elevation myocardial infarction (STEMI). The workshop discussed how conditioning has led to a significant and fundamental understanding of the mechanisms preventing cell death following ischaemia and reperfusion, and the key target cyto-protective pathways recruited by protective interventions, such as RIC. However, the obvious need to translate this protection to the clinical setting has not materialised largely due to the disconnect between preclinical and clinical studies. Discussion points included how to adapt preclinical animal studies to mirror the patient presenting with an acute myocardial infarction, as well as how to refine patient selection in clinical studies to account for co-morbidities and ongoing therapy. These latter scenarios can modify cytoprotective signalling and need to be taken into account to allow for a more robust outcome when powered appropriately. The workshop also discussed the potential for RIC in other disease settings including ischaemic stroke, cardio-oncology and COVID-19. The workshop, therefore, put forward specific classifications which could help identify so-called responders vs. non-responders in both the preclinical and clinical settings.


Asunto(s)
Isquemia Encefálica , COVID-19 , Precondicionamiento Isquémico Miocárdico , Accidente Cerebrovascular , Animales , Educación , Isquemia , Resultado del Tratamiento
3.
Br J Surg ; 108(11): 1332-1340, 2021 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-34476473

RESUMEN

BACKGROUND: Trials typically group cancers of the gastro-oesophageal junction (GOJ) with oesophageal or gastric cancer when studying neoadjuvant chemoradiation and perioperative chemotherapy, so the results may not be fully applicable to GOJ cancer. Because optimal neoadjuvant treatment for GOJ cancer remains controversial, outcomes with neoadjuvant chemoradiation versus chemotherapy for locally advanced GOJ adenocarcinoma were compared retrospectively. METHODS: Data were collected from all patients who underwent neoadjuvant treatment followed by surgery for adenocarcinoma located at the GOJ at a single high-volume institution between 2002 and 2017. Postoperative major complications and mortality were compared between groups using Fisher's exact test. Overall survival (OS) and disease-free survival (DFS) were assessed by log rank test and multivariable Cox regression analyses. Cumulative incidence functions were used to estimate recurrence, and groups were compared using Gray's test. RESULTS: Of 775 patients, 650 had neoadjuvant chemoradiation and 125 had chemotherapy. These groups were comparable in terms of clinical tumour and lymph node categories, although the chemoradiation group had greater proportions of white men, complete pathological response to chemotherapy, and smaller proportions of diffuse cancer, poor differentiation, and neurovascular invasion. Postoperative major complications (20.0 versus 17.6 per cent) and 30-day mortality (1.7 versus 1.6 per cent) were not significantly different between the chemoradiation and chemotherapy groups. After adjustment, type of therapy (chemoradiation versus chemotherapy) was not significantly associated with OS (hazard ratio (HR) 1.26, 95 per cent c.i. 0.96 to 1.67) or DFS (HR 1.27, 0.98 to 1.64). Type of recurrence (local, regional, or distant) did not differ after neoadjuvant chemoradiation versus chemotherapy. CONCLUSION: In patients undergoing surgical resection for locally advanced adenocarcinoma of the GOJ, OS and DFS did not differ significantly between patients who had neoadjuvant chemoradiation compared with chemotherapy.


Treating advanced cancer of the gastro-oesophageal junction (GOJ) poses a challenge given its location in the distal oesophagus and proximal stomach, and whether it should be treated as oesophageal or gastric cancer. Given the indistinct location, it is unclear whether GOJ cancer should be treated with neoadjuvant chemoradiation, which is the treatment of choice for advanced oesophageal cancers, or perioperative chemotherapy, which is the treatment of choice for advanced gastric cancers. Few studies have addressed treatment options specifically for GOJ cancers. This study investigated whether there was a difference in survival between patients with GOJ cancer who were treated with chemoradiation versus chemotherapy.


Asunto(s)
Adenocarcinoma/terapia , Antineoplásicos/uso terapéutico , Neoplasias Esofágicas/terapia , Esofagectomía/efectos adversos , Unión Esofagogástrica , Estadificación de Neoplasias , Adenocarcinoma/diagnóstico , Adenocarcinoma/mortalidad , Anciano , Quimioradioterapia Adyuvante , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , New York/epidemiología , Complicaciones Posoperatorias/epidemiología , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia/tendencias
4.
Diabet Med ; 37(8): 1230-1233, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32426859

RESUMEN

In the 25 years since the hypothesis was first described, therapeutic use of inhibitors of dipeptidyl peptidase-4 (DPP-4i) as a novel approach to the treatment of type 2 diabetes has become established widely, with several compounds now available to exemplify the class. Although the clinical profiles of members of the DPP-4i class have been reviewed extensively, the underlying pragmatic small molecular design and pharmaceutical properties of these agents have seldom been addressed in the context of establishment of the class as treatments for type 2 diabetes. Among the reasons contributing to the wide acceptance of DPP-4i as oral anti-hyperglycaemic therapy are: (i) the endocrine basis of their pharmacology; (ii) their chemical 'simplicity' and low molecular mass; (iii) their pharmacological selectivity for their target mechanism of action; (iv) the nature of physiologically relevant substrates for the enzyme; (v) their relative ease of formulation into tablets; (vi) their efficacy as glucose-lowering agents; (vii) their absorption, distribution, metabolism and elimination profiles; and (viii) their limited tolerability issues.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Diabetes Mellitus Tipo 2/metabolismo , Diseño de Fármacos , Humanos
5.
Phys Rev Lett ; 123(13): 131801, 2019 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-31697542

RESUMEN

We report the first measurement of the double-differential and total muon neutrino charged current inclusive cross sections on argon at a mean neutrino energy of 0.8 GeV. Data were collected using the MicroBooNE liquid argon time projection chamber located in the Fermilab Booster neutrino beam and correspond to 1.6×10^{20} protons on target of exposure. The measured differential cross sections are presented as a function of muon momentum, using multiple Coulomb scattering as a momentum measurement technique, and the muon angle with respect to the beam direction. We compare the measured cross sections to multiple neutrino event generators and find better agreement with those containing more complete treatment of quasielastic scattering processes at low Q^{2}. The total flux integrated cross section is measured to be 0.693±0.010(stat)±0.165(syst)×10^{-38} cm^{2}.

6.
Phys Rev Lett ; 118(22): 221803, 2017 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-28621993

RESUMEN

The MiniBooNE-DM Collaboration searched for vector-boson mediated production of dark matter using the Fermilab 8-GeV Booster proton beam in a dedicated run with 1.86×10^{20} protons delivered to a steel beam dump. The MiniBooNE detector, 490 m downstream, is sensitive to dark matter via elastic scattering with nucleons in the detector mineral oil. Analysis methods developed for previous MiniBooNE scattering results were employed, and several constraining data sets were simultaneously analyzed to minimize systematic errors from neutrino flux and interaction rates. No excess of events over background was observed, leading to a 90% confidence limit on the dark matter cross section parameter, Y=ε^{2}α_{D}(m_{χ}/m_{V})^{4}≲10^{-8}, for α_{D}=0.5 and for dark matter masses of 0.01

7.
Clin Exp Dermatol ; 42(8): 881-886, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28748571

RESUMEN

Porokeratosis, a disorder of keratinisation, is clinically characterized by the presence of annular plaques with a surrounding keratotic ridge. Clinical variants include linear, disseminated superficial actinic, verrucous/hypertrophic, disseminated eruptive, palmoplantar and porokeratosis of Mibelli (one or two typical plaques with atrophic centre and guttered keratotic rim). All of these subtypes share the histological feature of a cornoid lamella, characterized by a column of 'stacked' parakeratosis with focal absence of the granular layer, and dysmaturation (prematurely keratinised cells in the upper spinous layer). In recent years, a proposed new subtype, follicular porokeratosis (FP_, has been described, in which the cornoid lamella are exclusively located in the follicular ostia. We present four new cases that showed typical histological features of FP.


Asunto(s)
Folículo Piloso/patología , Poroqueratosis/patología , Piel/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Lentigo/complicaciones , Lentigo/patología , Masculino , Persona de Mediana Edad , Poroqueratosis/clasificación , Poroqueratosis/complicaciones
8.
Basic Res Cardiol ; 111(4): 41, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27164905

RESUMEN

In the 30 years since the original description of ischaemic preconditioning, understanding of the pathophysiology of ischaemia/reperfusion injury and concepts of cardioprotection have been revolutionised. In the same period of time, management of patients with coronary artery disease has also been transformed: coronary artery and valve surgery are now deemed routine with generally excellent outcomes, and the management of acute coronary syndromes has seen decade on decade reductions in cardiovascular mortality. Nonetheless, despite these improvements, cardiovascular disease and ischaemic heart disease in particular, remain the leading cause of death and a significant cause of long-term morbidity (with a concomitant increase in the incidence of heart failure) worldwide. The need for effective cardioprotective strategies has never been so pressing. However, despite unequivocal evidence of the existence of ischaemia/reperfusion in animal models providing a robust rationale for study in man, recent phase 3 clinical trials studying a variety of cardioprotective strategies in cardiac surgery and acute ST-elevation myocardial infarction have provided mixed results. The investigators meeting at the Hatter Cardiovascular Institute workshop describe the challenge of translating strong pre-clinical data into effective clinical intervention strategies in patients in whom effective medical therapy is already altering the pathophysiology of ischaemia/reperfusion injury-and lay out a clearly defined framework for future basic and clinical research to improve the chances of successful translation of strong pre-clinical interventions in man.


Asunto(s)
Daño por Reperfusión Miocárdica , Investigación Biomédica Traslacional , Animales , Humanos , Precondicionamiento Isquémico Miocárdico/métodos , Precondicionamiento Isquémico Miocárdico/tendencias
9.
Diabet Med ; 33(6): 718-22, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26773271

RESUMEN

The dipeptidyl peptidase-4 (DPP-4) inhibitor concept is an example of prospective drug design and development based upon a distinct endocrine hypothesis. The design of enzyme inhibitors is a pragmatic approach to drug design; being compatible with the identification and optimization of small molecules that have properties commensurate with oral administration, as well as acceptable drug metabolism, distribution and elimination characteristics. Glucagon-like peptide 1 (GLP-1), a hormone with a spectrum of favourable metabolic actions, including glucose-dependent stimulation of insulin and inhibition of glucagon secretion, provided the endocrine basis from which the idea of using DPP-4 inhibitors as anti-diabetic agents was developed. The origin of the DPP-4 inhibitor concept was inspired by the angiotensin-converting enzyme inhibitor approach, which succeeded in establishing a class of extensively used therapeutic agents for the treatment of cardiovascular disorders.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Descubrimiento de Drogas/tendencias , Difusión de Innovaciones , Predicción , Péptido 1 Similar al Glucagón/antagonistas & inhibidores , Humanos , Sistema Renina-Angiotensina/efectos de los fármacos
14.
Phys Rev Lett ; 112(6): 061801, 2014 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24580686

RESUMEN

A measurement of the energy dependence of antineutrino disappearance at the Daya Bay reactor neutrino experiment is reported. Electron antineutrinos (ν¯(e)) from six 2.9 GW(th) reactors were detected with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls. Using 217 days of data, 41 589 (203 809 and 92 912) antineutrino candidates were detected in the far hall (near halls). An improved measurement of the oscillation amplitude sin(2)2θ(13)=0.090(-0.009)(+0.008) and the first direct measurement of the ν¯(e) mass-squared difference |Δm(ee)2|=(2.59(-0.20)(+0.19))×10(-3) eV2 is obtained using the observed ν¯(e) rates and energy spectra in a three-neutrino framework. This value of |Δm(ee)2| is consistent with |Δm(µµ)2| measured by muon neutrino disappearance, supporting the three-flavor oscillation model.

16.
Clin Exp Dermatol ; 39(3): 310-4, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24635067

RESUMEN

Dyskeratosis congenita (DC) is a clinically and genetically heterogeneous multisystem bone marrow failure disorder of telomere maintenance, which may present with dermatological features. The main cause of mortality is bone marrow failure, often developing in the second decade of life, although pulmonary disease and malignancies such as squamous cell carcinomas (SCCs) may also prove fatal. We report the case of a 28-year-old man with X-linked DC and confirmed DKC1 gene mutation. In addition to the classic triad of nail dystrophy, hyperpigmentation and oral leucoplakia, the patient had actinic keratosis (AK) and photodamaged skin, hitherto under-recognized features of this condition. Awareness of the clinical presentation of DC is important, as accurate clinical and molecular diagnosis affords patients and their families genetic counselling, cancer prevention and screening measures, and planning for complications such as bone marrow failure.


Asunto(s)
Disqueratosis Congénita/patología , Queratosis Actínica/patología , Enfermedades del Aparato Lagrimal/patología , Envejecimiento de la Piel/patología , Adulto , Humanos , Masculino , Luz Solar/efectos adversos
17.
Radiography (Lond) ; 30(5): 1243-1248, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38959619

RESUMEN

INTRODUCTION: Advanced practice is well established in the health professions with multiprofessional capabilities in place in England. To recognise achievement of these capabilities an ePortfolio (supported) route was initiated in 2022. This study aimed to review the demographics and experiences of radiographers applying for recognition in the first year of operation. METHODS: The multi method evaluation consisted of quantitative data analysis of information regarding the first three cohorts of radiographers (n = 40) participating in the NHS England (NHSE) scheme. Interviews with 12 participants was undertaken with thematic analysis of the transcripts. RESULTS: Self-rated scores of expertise were significantly higher by therapeutic radiographers (n = 8) compared to their 32 diagnostic colleagues (t = 5.556; p < 0.01). Radiographers saw the ePortfolio as an opportunity to validate their experience and to evidence parity with other professions. Participants felt the process also enabled critical reflection and gave unseen insight into themselves and their roles. The support of experienced educational supervisors was felt to be vital in this process and for successful completion of portfolio. CONCLUSIONS: Several radiographers have now achieved the necessary standards to achieve NHSE recognition. The evaluation exposed that most radiographers did not have the relevant evidence to hand and the ongoing collection of evidence around capabilities and impact is critical to evidencing advanced practice capabilities. IMPLICATIONS FOR PRACTICE: Radiographers are able to achieve the capabilities expected for multiprofessional practice. Cultural change is required to normalise recording of evidence within practice including case-based discussions, clinical supervision and feedback from colleagues and patients. The support of an experienced educational supervisor aided the critical reflection on practice level.

19.
Diabetes Obes Metab ; 15(6): 531-7, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23331498

RESUMEN

AIM: Recent studies suggest that the incretin concept is not restricted to glucose ingestion but relevant also after non-glucose macronutrient administration. We therefore hypothesized that raising incretin hormones reduces circulating glucose after both glucose and non-glucose macronutrient ingestion in healthy subjects. METHODS: Twelve healthy subjects received the dipeptidyl peptidase-4 inhibitor sitagliptin (100 mg) or placebo before ingestion of glucose, fat (olive oil) or protein mix in equicaloric amounts (8 kcal/kg) plus paracetamol (1.5 g). The 120-min areas under curve (AUC) of intact glucagon-like peptide-1 (GLP-1), glucose, insulin, C-peptide, glucagon and paracetamol, and model-derived insulin secretion rate (ISR), insulin sensitivity, insulin clearance and glucose absorption were measured. RESULTS: The increased plasma intact GLP-1 levels after each macronutrient was augmented by sitagliptin. This was associated with a robust lowering of glucose: glucose excursion after oral glucose was diminished, and glucose fell below baseline after oral fat and protein. In spite of lower glucose, AUCC -peptide and ISR did not differ significantly between sitagliptin and placebo after any macronutrient. AUCglucagon , insulin sensitivity and insulin clearance were also not different between sitagliptin and placebo. Glucose absorption after oral glucose was reduced by sitagliptin, whereas AUCparacetamol was not statistically different between sitagliptin and placebo. CONCLUSIONS: Physiological elevation of intact GLP-1 levels after ingestion of glucose and non-glucose macronutrients is robustly glucose-lowering in healthy subjects. Hence, the incretin concept is not restricted to glucose ingestion in normal physiology. The glucose-lowering action of sitagliptin at these low glucose levels in healthy subjects may have complex mechanisms, involving both islet-dependent and islet-independent mechanisms.


Asunto(s)
Glucemia/efectos de los fármacos , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Inhibidores de la Dipeptidil-Peptidasa IV/administración & dosificación , Insulina/metabolismo , Pirazinas/administración & dosificación , Triazoles/administración & dosificación , Adulto , Glucemia/metabolismo , Prueba de Tolerancia a la Glucosa , Humanos , Resistencia a la Insulina/fisiología , Secreción de Insulina , Células Secretoras de Insulina , Masculino , Micronutrientes/administración & dosificación , Fosfato de Sitagliptina , Resultado del Tratamiento
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