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1.
BJOG ; 127(6): 694-700, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32011073

RESUMEN

BACKGROUND: Developing a shared agenda is an important step in ensuring future research has the necessary relevance. OBJECTIVE: To characterise research priority setting partnerships (PSPs) relevant to women's health. SEARCH STRATEGY: Included studies were identified by searching MEDLINE and the James Lind Alliance (JLA) database. SELECTION CRITERIA: Priority setting partnerships using formal consensus methods. DATA COLLECTION AND ANALYSIS: Descriptive narrative to describe the study characteristics, methods, and results. MAIN RESULTS: Ten national and two international PSPs were identified. All PSPs used the JLA method to identify research priorities. Nine PSPs had published a protocol. Potential research uncertainties were gathered from guidelines (two studies), Cochrane reviews (five studies), and surveys (12 studies). The number of healthcare professionals (31-287), patients (44-932), and others (33-139) who responded to the survey, and the number of uncertainties submitted (52-4767) varied. All PSPs entered confirmed research uncertainties (39-104) into interim priority setting surveys and healthcare professionals (31-287), patients (44-932), and others (33-139) responded. All PSPs entered a short list of research uncertainties into a consensus development meeting, which enabled healthcare professionals (six to 21), patients (eight to 14), and others (two to 13) to identify research priorities (ten to 15). Four PSPs have published their results. CONCLUSION: Future research priority setting studies should publish a protocol, use formal consensus development methods, and ensure their methods and results are comprehensively reported. TWEETABLE ABSTRACT: Research published in @BJOGtweets highlights future research priorities across women's health, including @FertilityTop10, @jamesmnduffy.


Asunto(s)
Investigación Biomédica/organización & administración , Investigación , Salud de la Mujer , Consenso , Femenino , Humanos , Proyectos Piloto , Salud de la Mujer/estadística & datos numéricos
2.
J Acoust Soc Am ; 145(3): 1401, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-31067938

RESUMEN

To understand the consequences of underwater noise exposure for cetaceans, there is a need for assessments of behavioural responses over increased spatial and temporal scales. Bottom-moored acoustic recorders and satellite tags provide such long-term and large spatial coverage of behaviour compared to short-duration acoustic-recording tags. However, these tools result in a decreased resolution of data from which an animal response can be inferred, and no direct recording of the sound received at the animal. This study discusses the consequence of the decreased resolution of data from satellite tags and fixed acoustic recorders on the acoustic dose estimated by propagation modelling and presents a method for estimating the range of sound levels that animals observed with these methods have received. This problem is illustrated using experimental results obtained during controlled exposures of northern bottlenose whales (Hyperoodon ampullatus) exposed to naval sonar, carried out near Jan Mayen, Norway. It is shown that variability and uncertainties in the sound field, resulting from limited sampling of the acoustic environment, as well as decreased resolution in animal locations, can lead to quantifiable uncertainties in the estimated acoustic dose associated with the behavioural response (in this case avoidance and cessation of foraging).


Asunto(s)
Acústica/instrumentación , Ecolocación , Comunicaciones por Satélite/instrumentación , Ballenas/fisiología , Animales , Comunicaciones por Satélite/normas
3.
Ultrasound Obstet Gynecol ; 51(1): 110-117, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29055072

RESUMEN

OBJECTIVES: To assess the prevalence of congenital uterine anomalies, including arcuate uterus, and their effect on reproductive outcome in subfertile women undergoing assisted reproduction. METHODS: Consecutive women referred for subfertility between May 2009 and November 2015 who underwent assisted reproduction were included in the study. As part of the initial assessment, each woman underwent three-dimensional transvaginal sonography. Uterine morphology was classified using the modified American Fertility Society (AFS) classification of congenital uterine anomalies proposed by Salim et al. If the external contour of the uterus was uniformly convex or had an indentation of < 10 mm, but there was a cavity indentation, it was defined as arcuate or septate. Arcuate uterus was further defined as the presence of a concave fundal indentation with a central point of indentation at an obtuse angle. Subseptate uterus was defined as the presence of a septum, not extending to the cervix, with the central point of the septum at an acute angle; if the septum extended to the internal cervical os, the uterus was defined as septate. Reproductive outcomes, including live birth, clinical pregnancy and preterm birth, were compared between women with a normal uterus and those with a congenital uterine anomaly. Subgroup analysis by type of uterine morphology and logistic regression analysis adjusted for age, body mass index, levels of anti-Müllerian hormone, antral follicle count and number and day of embryo transfer were performed. RESULTS: A total of 2375 women were included in the study, of whom 1943 (81.8%) had a normal uterus and 432 (18.2%) had a congenital uterine anomaly. The most common anomalies were arcuate (n = 387 (16.3%)) and subseptate (n = 16 (0.7%)) uterus. The rate of live birth was similar between women with a uterine anomaly and those with a normal uterus (35% vs 37%; P = 0.47). The rates of clinical pregnancy, mode of delivery and sex of the newborn were also similar between the two groups. Preterm birth before 37 weeks' gestation was more common in women with uterine anomalies than in controls (22% vs 14%, respectively; P = 0.03). Subgroup analysis by type of anomaly showed no difference in the incidence of live birth and clinical pregnancy for women with an arcuate uterus, but indicated worse pregnancy outcome in women with other major anomalies (P = 0.042 and 0.048, respectively). CONCLUSIONS: Congenital uterine anomalies as a whole, when defined using the modified AFS classification, do not affect clinical pregnancy or live-birth rates in women following assisted reproduction, but do increase the incidence of preterm birth. The presence of uterine abnormalities more severe than arcuate uterus significantly worsens all pregnancy outcomes. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Aborto Espontáneo/prevención & control , Transferencia de Embrión , Infertilidad Femenina , Ultrasonografía , Anomalías Urogenitales/diagnóstico por imagen , Útero/anomalías , Adulto , Transferencia de Embrión/métodos , Femenino , Humanos , Histeroscopía , Recién Nacido , Nacimiento Vivo , Embarazo , Resultado del Embarazo , Estudios Prospectivos , Anomalías Urogenitales/fisiopatología , Útero/diagnóstico por imagen , Útero/fisiopatología
4.
Neuroimage ; 157: 500-510, 2017 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-28633971

RESUMEN

Application of functional imaging techniques to animal models is vital to understand pain mechanisms, but is often confounded by the need to limit movement artefacts with anaesthesia, and a focus on evoked responses rather than clinically relevant spontaneous pain and related hyperalgesia. The aim of the present study was to investigate the potential of manganese-enhanced magnetic resonance imaging (MEMRI) to measure neural responses during on-going pain that underpins hyperalgesia in pre-clinical models of nociception. As a proof of concept that MEMRI is sensitive to the neural activity of spontaneous, intermittent behaviour, we studied a separate positive control group undergoing a voluntary running wheel experiment. In the pain models, pain behaviour (weight bearing asymmetry and hindpaw withdrawal thresholds (PWTs)) was measured at baseline and following either intra-articular injection of nerve growth factor (NGF, 10µg/50µl; acute pain model, n=4 rats per group), or the chondrocyte toxin monosodium iodoacetate (MIA, 1mg/50µl; chronic model, n=8 rats per group), or control injection. Separate groups of rats underwent a voluntary wheel running protocol (n=8 rats per group). Rats were administered with paramagnetic ion Mn2+ as soluble MnCl2 over seven days (subcutaneous osmotic pump) to allow cumulative activity-dependent neural accumulation in the models of pain, or over a period of running. T1-weighted MR imaging at 7T was performed under isoflurane anaesthesia using a receive-only rat head coil in combination with a 72mm volume coil for excitation. The pain models resulted in weight bearing asymmetry (NGF: 20.0 ± 5.2%, MIA: 15 ± 3%), and a reduction in PWT in the MIA model (8.3 ± 1.5g) on the final day of assessment before undergoing MR imaging. Voxel-wise and region-based analysis of MEMRI data did not identify group differences in T1 signal. However, MnCl2 accumulation in the VTA, right Ce amygdala, and left cingulate was negatively correlated with pain responses (greater differences in weight bearing), similarly MnCl2 accumulation was reduced in the VTA in line with hyperalgesia (lower PWTs), which suggests reduced regional activation as a result of the intensity and duration of pain experienced during the 7 days of MnCl2 exposure. Motor cortex T1-weighted signal increase was associated with the distance ran in the wheel running study, while no between group difference was seen. Our data suggest that on-going pain related signal changes identified using MEMRI offers a new window to study the neural underpinnings of spontaneous pain in rats.


Asunto(s)
Dolor Agudo/fisiopatología , Artralgia/fisiopatología , Conducta Animal/fisiología , Cerebro/fisiopatología , Dolor Crónico/fisiopatología , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Manganeso , Dolor Agudo/diagnóstico por imagen , Animales , Artralgia/diagnóstico por imagen , Cerebro/diagnóstico por imagen , Dolor Crónico/diagnóstico por imagen , Modelos Animales de Enfermedad , Masculino , Ratas , Ratas Sprague-Dawley
5.
BJOG ; 124(7): 1008-1015, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28318099

RESUMEN

BACKGROUND: Progestogens have been evaluated in numerous trials and meta-analyses, many of which concluded they were effective. However, two large trials PROMISE and OPPTIMUM have recently concluded that progesterone was ineffective. This raises the possibility that earlier studies and reviews had been biased by either selective publication or selective choice of outcomes, so called "P-hacking". OBJECTIVES: To compare the findings all progestogen trials and systematic reviews with those of trials with pre-registered primary outcomes which avoided selective outcome reporting. SEARCH STRATEGY: Search of PubMed, the Cochrane Library and trial registries. Registration PROSPERO CRD42016035303. SELECTION CRITERIA: Systematic reviews of randomised trials comparing progestogen with placebo in pregnancy and the individual trials included in those reviews. The subset of trials reporting a pre-registered primary outcome were compared with the totality of trials and reviews. DATA COLLECTION AND ANALYSIS: For reviews all outcomes were included. For individual trials all outcomes reported in the systematic reviews were included. For the comparison group we recorded the registered primary outcome from trials that were either registered before they started, or registered during the recruitment phase and also double blind. MAIN RESULTS: Nineteen of twenty-nine meta-analyses concluded that progestogens were effective. Twenty-two trials reported their pre-registered primary outcomes. There was no effect of progesterone on primary registered dichotomous outcome RR 1.00 (95% CI 0.94-1.07). Only one of the 22 showed a nominally statistically significant benefit. AUTHOR'S CONCLUSIONS: When evaluated in registered double-blind trials with analysis restricted to predefined primary outcomes, progestational agents in pregnancy are ineffective. TWEETABLE ABSTRACT: Progestogens to prevent pregnancy loss, an example of P-hacking.


Asunto(s)
Sesgo , Complicaciones del Embarazo , Resultado del Embarazo , Progesterona , Proyectos de Investigación , Femenino , Humanos , Embarazo , Ensayos Clínicos como Asunto , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/prevención & control , Resultado del Embarazo/epidemiología , Progesterona/uso terapéutico , Revisiones Sistemáticas como Asunto
6.
Br J Surg ; 103(4): 374-81, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26805720

RESUMEN

BACKGROUND: The aim of this study was to assess behavioural recovery from the patient's perspective as a prespecified secondary outcome in a multicentre parallel-group randomized clinical trial comparing ultrasound-guided foam sclerotherapy (UGFS), endovenous laser ablation (EVLA) and surgery for the treatment of primary varicose veins. METHODS: Participants were recruited from 11 UK sites as part of the CLASS trial, a randomized trial of UGFS, EVLA or surgery for varicose veins. Patients were followed up 6 weeks after treatment and asked to complete the Behavioural Recovery After treatment for Varicose Veins (BRAVVO) questionnaire. This is a 15-item instrument that covers eight activity behaviours (tasks or actions an individual is capable of doing in an idealized situation) and seven participation behaviours (what the individual does in an everyday, real-world situation) that were identified to be important from the patient's perspective. RESULTS: A total of 798 participants were recruited. Both UGFS and EVLA resulted in a significantly quicker recovery compared with surgery for 13 of the 15 behaviours assessed. UGFS was superior to EVLA in terms of return to full-time work (hazard ratio 1·43, 95 per cent c.i. 1·11 to 1·85), looking after children (1·45, 1·04 to 2·02) and walks of short (1·48, 1·19 to 1·84) and longer (1·32, 1·05 to 1·66) duration. CONCLUSION: Both UGFS and EVLA resulted in more rapid recovery than surgery, and UGFS was superior to EVLA for one-quarter of the behaviours assessed. The BRAVVO questionnaire has the potential to provide important meaningful information to patients about their early recovery and what they may expect to be able to achieve after treatment.


Asunto(s)
Conducta/fisiología , Terapia por Láser/métodos , Calidad de Vida , Recuperación de la Función , Escleroterapia/métodos , Várices/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento , Várices/psicología , Adulto Joven
7.
Chem Res Toxicol ; 27(10): 1853-9, 2014 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-25222830

RESUMEN

The chemical reactivity of styrene-7,8-oxide (SO), an alkylating agent with high affinity for the guanine­N7 position and a probable carcinogen for humans, with 4-(p-nitrobenzyl)pyridine (NBP), a trap for alkylating agents with nucleophilic characteristics similar to those of DNA bases, was investigated kinetically in water/dioxane media. UV­vis spectrophotometry and ultrafast liquid chromatography were used to monitor the reactions involved. It was found that in the alkylation process four reactions occur simultaneously: (a) the formation of a ß-NBP­SO adduct through an SN2 mechanism; (b) the acid-catalyzed formation of the stable α-NBP­SO adduct through an SN2' mechanism; (c) the base-catalyzed hydrolysis of the ß-adduct, and (d) the acid-catalyzed hydrolysis of SO. At 37.5 °C and pH = 7.0 (in 7:3 water/dioxane medium), the values of the respective reaction rate constants were as follows: kalkß = (2.1 ± 0.3) × 10­4 M­1 s­1, kalkα = (1.0 ± 0.1) × 10­4 M­1 s­1, khydAD = (3.06 ± 0.09) × 10­6 s­1, and khyd = (4.2 ± 0.9) × 10­6 s­1. These values show that, in order to determine the alkylating potential of SO, none of the four reactions involved can be neglected. Temperature and pH were found to exert a strong influence on the values of some parameters that may be useful to investigate possible chemicobiological correlations (e.g., in the pH 5.81­7.69 range, the fraction of total adducts formed increased from 24% to 90% of the initial SO, whereas the adduct lifetime of the unstable ß-adduct, which gives an idea of the permanence of the adduct over time, decreased from 32358 to 13313 min). A consequence of these results is that the conclusions drawn in studies addressing alkylation reactions at temperatures and/or pH far from those of biological conditions should be considered with some reserve.


Asunto(s)
Alquilantes/química , Compuestos Epoxi/química , Piridinas/química , Alquilación , Catálisis , Dioxanos/química , Concentración de Iones de Hidrógeno , Cinética , Temperatura , Agua/química
8.
Eur J Oncol Nurs ; 71: 102610, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38914026

RESUMEN

INTRODUCTION: Healthcare professionals are vital in preparing people living with and beyond cancer about the risks of chronic pain after cancer treatment. To do so, healthcare professionals need to be knowledgeable and confident about chronic pain after cancer treatment, yet little is known about their understanding or confidence of this common long-term and late side effect of cancer treatment. AIM: To identify healthcare professionals' knowledge and understanding of chronic pain after cancer treatment and consider how confident they are to inform, listen and signpost people living with and beyond cancer to appropriate information and support. METHOD: A cross sectional online survey was distributed to healthcare professionals in the UK via cancer and primary care networks, cancer alliances and social media. The survey consisted of four domains: 1) knowledge and understanding, 2) information and support, 3) confidence and 4) barriers. Quantitative data were analysed with descriptive statistics and free text comments were analysed using qualitative content analysis. RESULTS: Healthcare professionals reported limited knowledge and understanding of chronic pain after cancer treatment. Healthcare professionals lacked confidence to talk to people about chronic pain after cancer treatment and viewed their lack of knowledge as a barrier. Additional barriers included 'Limited service provision', 'Conflict between services', 'Not my role' and 'Challenges in diagnosing chronic pain in cancer survivors'. CONCLUSION: Chronic pain after cancer can be a significant issue for those living with and beyond cancer, yet healthcare professionals report limited knowledge of it or understanding of the impact. More education is needed to increase healthcare professionals' knowledge and confidence in chronic pain after cancer treatment.


Asunto(s)
Dolor Crónico , Conocimientos, Actitudes y Práctica en Salud , Neoplasias , Humanos , Estudios Transversales , Reino Unido , Dolor Crónico/terapia , Masculino , Femenino , Neoplasias/complicaciones , Encuestas y Cuestionarios , Adulto , Persona de Mediana Edad , Personal de Salud/psicología , Manejo del Dolor/métodos , Actitud del Personal de Salud
9.
Plant Cell Environ ; 36(4): 869-78, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23057760

RESUMEN

An electrochemical approach to directly measure the dynamic process of H2 O2 release from cultures of Arabidopsis thaliana cells is reported. This approach is based on H2 O2 oxidation on a Pt electrode in conjunction with continuous measurement of sample pH. For [H2 O2 ] <1 mm, calibration plots were linear and the amperometric response of the electrode was maximum at pH 6. At higher concentrations ([H2 O2 ] >1 mm), the amperometric response can be described by Michaelian-type kinetics and a mathematical expression relating current intensity and pH was obtained to quantitatively determine H2 O2 concentration. At pH 5.5, the detection limit of the sensor was 3.1 µm (S/N = 3), with a response sensitivity of 0.16 Am(-1 ) cm(-2) and reproducibility was within 6.1% in the range 1-5 × 10(-3 ) m (n = 5). Cell suspensions under normal physiological conditions had a pH between 5.5-5.7 and H2 O2 concentrations in the range 7.0-20.5 µm (n = 5). The addition of exogenous H2 O2 , as well as other potential stress stimuli, was made to the cells and the change in H2 O2 concentration was monitored. This real-time quantitative H2 O2 analysis is a potential marker for the evaluation of oxidative stress in plant cell cultures.


Asunto(s)
Arabidopsis/metabolismo , Técnicas Electroquímicas/instrumentación , Peróxido de Hidrógeno/análisis , Estrés Oxidativo , Arabidopsis/fisiología , Biomarcadores/metabolismo , Calibración , Catalasa , Técnicas de Cultivo de Célula , Técnicas Electroquímicas/métodos , Electrodos , Fertilizantes , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/farmacología , Concentración de Iones de Hidrógeno , Insecticidas , Metales , Oxidación-Reducción , Platino (Metal) , Reproducibilidad de los Resultados , Sales (Química) , Sensibilidad y Especificidad , Factores de Tiempo
10.
Chem Res Toxicol ; 25(12): 2755-62, 2012 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-23171086

RESUMEN

The chemical reactivity of the mutagenic epoxides (EP) propylene oxide (PO), 1,2-epoxybutane (1,2-EB), and cis- and trans-2,3-epoxybutane (cis- and trans-2,3-EB) with 4-(p-nitrobenzyl)pyridine (NBP), a bionucleophile model for S(N)2 alkylating agents with high affinity for the guanine-N7 position, was investigated kinetically. It was found that three reactions are involved simultaneously: the alkylation reaction of NBP by EP, which yields the corresponding NBP-EP adducts through an S(N)2 mechanism, and EP and NBP-EP hydrolysis reactions. PO and 1,2-EB were seen to exhibit a higher alkylating potential than cis- and trans-2,3-EB. From a study of the correlations between the chemical reactivity (kinetic parameters) and the biological effectiveness of oxiranes, the following conclusions can be drawn: (i) the hydrolysis reactions of epoxides must be taken into account to understand their bioactivity. (ii) The fraction (f) of the alkylating oxirane that forms the adduct and the adduct life (AL) permit the potential of epoxides as bioactive molecules to be rationalized even semiquantitatively; and (iii) alkylation of DNA by epoxides and the O(6)-/N7-guanine adduct ratio are directly related to their mutagenicity in vitro.


Asunto(s)
Compuestos Epoxi/química , Piridinas/química , Alquilantes , Aductos de ADN , Compuestos Epoxi/metabolismo , Cinética , Piridinas/metabolismo
12.
Cardiovasc Drugs Ther ; 26(5): 401-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22936457

RESUMEN

INTRODUCTION: Chronic critical limb ischemia (CLI) is a severe condition of hypo-perfusion of lower limbs, which is associated with inflammation and a pro-coagulative state. It is a disease at high risk of amputation and cardiovascular death. Propionyl-L-carnitine (PLC) is efficacious in improving pain free walking distance in peripheral arterial disease with claudication; it also exerts favorable effects on the arterial wall and on endothelial function. The purpose of this study was to evaluate the effects of PLC on microcirculation, endothelial function and pain relief in patients affected by CLI not suitable for surgical intervention. PATIENTS AND METHODS: We enrolled 48 patients with CLI. Patients were randomized into two groups: the first group was treated with PLC, the second was treated with saline solution. All of them underwent the following tests: laser Doppler flowmetry at the forefoot at rest and after ischemia, trans cutaneous oxygen partial pressure and carbon dioxide partial pressure at the forefoot at rest and after ischemia, endothelium dependent dilation of the brachial artery. All tests were repeated after treatments. Pain was assessed by visual analog pain scale. RESULTS: Endothelium dependent dilation increased after PLC (9.5 ± 3.2 vs 4.9 ± 1.4 %; p < 0.05). Post-ischemic peak flow with laser-Doppler flow increased after PLC. TcPO2 increased, while TcPCO2 decreased after PLC; CO2 production decreased after PLC. VAS showed a significant reduction in pain perception after active treatment. CONCLUSIONS: In CLI patients, PLC can improve microcirculation (post ischemic hyperemia, TcPO2 and TcPCO2 production). PLC also enhances endothelium dependent dilation and reduces analgesic consumption and pain perception.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Carnitina/análogos & derivados , Isquemia/tratamiento farmacológico , Enfermedad Arterial Periférica/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Antiinflamatorios no Esteroideos/farmacología , Monitoreo de Gas Sanguíneo Transcutáneo , Arteria Braquial/fisiología , Carnitina/farmacología , Carnitina/uso terapéutico , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiopatología , Femenino , Humanos , Isquemia/fisiopatología , Flujometría por Láser-Doppler , Pierna/irrigación sanguínea , Masculino , Microcirculación/efectos de los fármacos , Manejo del Dolor , Enfermedad Arterial Periférica/fisiopatología , Flujo Sanguíneo Regional/efectos de los fármacos , Vasodilatación/efectos de los fármacos
13.
Org Biomol Chem ; 9(20): 7016-22, 2011 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-21870002

RESUMEN

The alkylating potential of p-nitrostyrene oxide (pNSO)--a compound used as a substrate to study the activity of epoxide hydrolases as well as in polymer production and in the pharmaceutical industry--was investigated kinetically. The molecule 4-(p-nitrobenzyl)pyridine (NBP), as a model nucleophile for DNA bases, was used as an alkylation substrate. In order to gain insight into the effect of the hydrolysis of pNSO, as well as the hydrolysis of the NBP-pNSO adduct on the pNSO alkylating efficiency, these two competing reactions were studied in parallel with the main NBP-alkylation reaction. The following conclusions were drawn: (i) pNSO reacts through an S(N)2 mechanism, with NBP to form an adduct, pNSO-NBP (AD). The rate equation for the adduct formation is: r = d[AD]/dt = k(alk)[NBP][pNSO]-k(hyd)(AD) [AD] (k(alk), and k(hyd)(AD) being the alkylation rate constant and the NBP-pNSO adduct hydrolysis rate constant, respectively); (ii) the alkylating capacity of pNSO, defined as the fraction of initial alkylating agent that forms the adduct, is similar to that of mutagenic agents as effective as ß-propiolactone. The instability of the pNSO-NBP adduct formed could be invoked to explain the lower mutagenicity shown by pNSO; (iii) the different stabilities of the α and ß-adducts formed between NBP and styrene oxides show that the alkylating capacity f = k(alk)[NBP]/(k(alk)[NBP] + k(hyd)) (k(hyd) being the pNSO hydrolysis rate constant) as well as the alkylating effectiveness, AL = f/k(hyd)(AD), are useful tools for correlating the chemical reactivity and mutagenicity of styrene oxides; (iv) a pNSO-guanosine adduct was detected.


Asunto(s)
Alquilantes/química , Materiales Biomiméticos/química , Compuestos Epoxi/química , Alquilación , Hidrólisis , Cinética , Estructura Molecular
14.
Neurologia (Engl Ed) ; 36(6): 403-411, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34238522

RESUMEN

OBJECTIVES: To describe non-relapse-related emergency consultations of patients with multiple sclerosis (MS): causes, difficulties in the diagnosis, clinical characteristics, and treatments administered. METHODS: We performed a retrospective study of patients who attended a multiple sclerosis day hospital due to suspected relapse and received an alternative diagnosis, over a 2-year period. Demographic data, clinical characteristics, final diagnosis, and treatments administered were evaluated. Patients who were initially diagnosed with pseudo-relapse and ultimately diagnosed with true relapse were evaluated specifically. As an exploratory analysis, patients who consulted with non-inflammatory causes were compared with a randomly selected cohort of patients with true relapses who attended the centre in the same period. RESULTS: The study included 50 patients (33 were women; mean age 41.4 ±â€¯11.7 years). Four patients (8%) were initially diagnosed with pseudo-relapse and later diagnosed as having a true relapse. Fever and vertigo were the main confounding factors. The non-inflammatory causes of emergency consultation were: neurological, 43.5% (20 patients); infectious, 15.2% (7); psychiatric, 10.9% (5); vertigo, 8.6% (4); trauma, 10.9% (5); and miscellaneous, 10.9% (5). CONCLUSIONS: MS-related symptoms constituted the most frequent cause of non-inflammatory emergency consultations. Close follow-up of relapse and pseudo-relapse is necessary to detect incorrect initial diagnoses, avoid unnecessary treatments, and relieve patients' symptoms.


Asunto(s)
Esclerosis Múltiple , Derivación y Consulta , Adulto , Enfermedad Crónica , Femenino , Humanos , Esclerosis Múltiple/diagnóstico , Recurrencia , Estudios Retrospectivos
15.
Polymers (Basel) ; 13(3)2021 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-33498770

RESUMEN

The effect of relative humidity (RH) and degree of sulfonation (DS) on the ionic conductivity and water uptake of proton-exchange membranes based on sulfonated multiblock copolymers composed of polysulfone (PSU) and polyphenylsulfone (PPSU) is examined experimentally and numerically. Three membranes with a different DS and ion-exchange capacity are analyzed. The heterogeneous structure of the membranes shows a random distribution of sulfonated (hydrophilic) and non-sulfonated (hydrophobic) domains, whose proton conductivity is modeled based on percolation theory. The mesoscopic model solves simplified Nernst-Planck and charge conservation equations on a random cubic network. Good agreement is found between the measured ionic conductivity and water uptake and the model predictions. The ionic conductivity increases with RH due to both the growth of the hydrated volume available for conduction and the decrease of the tortuosity of ionic transport pathways. Moreover, the results show that the ionic conductivity increases nonlinearly with DS, experiencing a strong rise when the DS is varied from 0.45 to 0.70, even though the water uptake of the membranes remains nearly the same. In contrast, the increase of the ionic conductivity between DS=0.70 and DS=0.79 is significantly lower, but the water uptake increases sharply. This is explained by the lack of microphase separation of both copolymer blocks when the DS is exceedingly high. Encouragingly, the copolymer membranes demonstrate a similar performance to Nafion under well hydrated conditions, which can be further optimized by a combination of numerical modeling and experimental characterization to develop new-generation membranes with better properties.

16.
J Org Chem ; 75(5): 1444-9, 2010 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-20121054

RESUMEN

The formation of chemical species with DNA-damaging and mutagenic activity for bacterial test systems was detected in sorbic acid-nitrite mixtures. 1,4-Dinitro-2-methylpyrrole (NMP), one the main products resulting from the reaction between sorbic acid and nitrite, has mutagenic properties, and here its alkylating capacity was investigated. The conclusions drawn are as follows: (i) In aqueous medium, after the addition of a hydroxide ion and the subsequent loss of nitrite, NMP affords 5-methyl-3-nitro-1H-pyrrol-2-ol. This species is in equilibrium with 5-methyl-3-nitro-1H-pyrrol-2(5H)-one, the effective alkylating agent responsible for the genotoxic capacity of NMP; (ii) 5-methyl-3-nitro-1H-pyrrol-2(5H)-one alkylates 4-(p-nitrobenzyl)pyridine (NBP), a molecule with nucleophilic characteristics similar to those of DNA bases, forming an adduct (AD; epsilon = 1.14 x 10(4) M(-1) cm(-1)); (iii) The calculated energy barrier for the alkylation of NBP for NMP and the value of the fraction of alkylating agent forming the adduct are consistent with the observed mutagenicity of NMP; (iv) The reactivity of NMP can be explained in terms of the instability of the N-NO(2) bond as well as the effect of this group on aromaticity.


Asunto(s)
Alquilantes/química , ADN/química , Mutágenos , Nitritos/química , Pirroles/química , Ácido Sórbico/química , Alquilantes/toxicidad , Cromatografía Líquida de Alta Presión , ADN/metabolismo , Daño del ADN , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Mutación/efectos de los fármacos , Pirroles/toxicidad , Salmonella , Espectrofotometría Ultravioleta , Relación Estructura-Actividad
17.
Nature ; 431(7007): 437-40, 2004 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-15386008

RESUMEN

All properties of molecules--from binding and excitation energies to their geometry--are determined by the highly correlated initial-state wavefunction of the electrons and nuclei. Details of these correlations can be revealed by studying the break-up of these systems into their constituents. The fragmentation might be initiated by the absorption of a single photon, by collision with a charged particle or by exposure to a strong laser pulse: if the interaction causing the excitation is sufficiently understood, the fragmentation process can then be used as a tool to investigate the bound initial state. The interaction and resulting fragment motions therefore pose formidable challenges to quantum theory. Here we report the coincident measurement of the momenta of both nuclei and both electrons from the single-photon-induced fragmentation of the deuterium molecule. The results reveal that the correlated motion of the electrons is strongly dependent on the inter-nuclear separation in the molecular ground state at the instant of photon absorption.

18.
Eur J Intern Med ; 77: 79-85, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32151490

RESUMEN

BACKGROUND: An abnormal ankle-brachial pressure index (ABI) is a marker of the risk for increased total and cardiovascular (CV) mortality. However, it is not clear whether it is associated with an even worse prognosis in patients with previous CV events or with cancer mortality. MATERIALS AND METHODS: Consecutive subjects undergoing ABI assessment for suspected peripheral artery disease or for stratification of CV risk in ten centers in the Veneto Region (northeast Italy), between 2011 and 2014 were enrolled. The ABI was expressed as normal ≥0.9 to ≤1.3, and abnormal <0.9 or >1.3. All-cause mortality and CV or cancer mortality and hospitalizations for CV disease were collected from administrative databases up to December 2018. RESULTS: The study enrolled 1,177 patients. ABI was abnormal in 57.2%. Median follow-up was 61.6 months (53.4-70.1). All-cause, CV and cancer mortality were higher in patients with abnormal than normal ABI, with hazard ratios (HR) respectively 2.0 (95% CI 1.48-2.69), 1.98 (95% CI 1.24-3.17) and 1.85 (95% CI 1.09-3.15). Among subjects with abnormal ABI, the risk of overall mortality, HR 1.57 (95% CI 1.17-2.12), and CV mortality, HR 2.39 (95% CI 1.43-3.99), was higher in those with previous CV events. These latter also had a higher risk of hospitalization for myocardial infarction and stroke: HR 1.85 (95% CI 1.023.37) and 2.17 (95% CI 1.10-4.28). CONCLUSIONS: The co-existence of abnormal ABI and a history of CV events identifies subjects at higher risk, who call for a more aggressive approach. Abnormal ABI is also a predictor of cancer mortality.


Asunto(s)
Enfermedades Cardiovasculares , Neoplasias , Índice Tobillo Braquial , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Italia/epidemiología , Valor Predictivo de las Pruebas , Pronóstico , Factores de Riesgo
19.
Neuropharmacology ; 56(2): 405-13, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18930746

RESUMEN

Tricyclic antidepressants (TCAs) are an important analgesic treatment for neuropathic pain, though the neural substrates mediating these effects are poorly understood. We have used an integrative approach combining behavioural pharmacology with functional magnetic resonance imaging (fMRI) to investigate the effects of chronic treatment with the TCA desipramine, on touch-evoked pain (mechanical allodynia) and brain regional activity in the selective spinal nerve ligation (SNL) model of neuropathic pain. SNL and sham-operated rats received once daily i.p. administration of 10 mg/kg DMI, or saline, for 14 days. Withdrawal responses to the application of a normally non-noxious (10 g) stimulus were recorded in SNL and sham-operated rats over this period. On the final day of the study, SNL and sham-operated rats received a final challenge dose of DMI (10 mg/kg i.p.) during fMRI scanning. Chronic administration of desipramine (DMI) significantly attenuated mechancial allodynia in SNL rats. DMI challenge in chronic DMI-treated neuropathic rats produced significantly greater activation of the deep mesencephalic nucleus, primary somatosensory cortex, insular cortex, medial globus pallidus, inferior colliculus, perirhinal cortex and cerebellum compared to sham-operated rats and saline controls. By contrast, the spatial pattern of brain regional activation by chronic DMI treatment in sham controls encompassed a number of other areas including those associated with learning and memory processes. These novel findings identify key brain regions implicated in the analgesic and mood altering effects associated with chronic treatment with DMI.


Asunto(s)
Mapeo Encefálico , Encéfalo/efectos de los fármacos , Desipramina/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Neuralgia/tratamiento farmacológico , Neuralgia/patología , Animales , Encéfalo/irrigación sanguínea , Encéfalo/patología , Modelos Animales de Enfermedad , Esquema de Medicación , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/etiología , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética , Masculino , Oxígeno/sangre , Umbral del Dolor/efectos de los fármacos , Estimulación Física/efectos adversos , Ratas , Ratas Sprague-Dawley , Nervios Espinales/fisiopatología
20.
Chem Res Toxicol ; 22(7): 1320-4, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19580248

RESUMEN

Because chemical species with DNA-damaging and mutagenic activity are formed in sorbate-nitrite mixtures and because sorbic acid sometimes coexists with nitrite occurring naturally or incorporated as a food additive, the study of sorbate-nitrite interactions is important. Here, the alkylating potential of the products resulting from such interactions was investigated. Drawn were the following conclusions: (i) Acetonitrile oxide (ACNO) is the compound responsible for the alkylating capacity of sorbate-nitrite mixtures; (ii) ACNO alkylates 4-(p-nitrobenzyl)pyridine (NBP), a trap for alkylating agents with nucleophilic characteristics similar to those of DNA bases, forming an adduct (AD; epsilon = 1.4 x 10(4) M(-1) cm(-1); lambda = 519 nm); (iii) the NBP alkylation reaction complies with the rate equation, r = d[AD]/dt = k(alk)(ACNO)[ACNO][NBP]-k(hyd)(AD)[AD], k(alk)(ACNO) being the NBP alkylation rate constant for ACNO and k(hyd)(AD) the rate constant for the adduct hydrolysis reaction; (iv) the small fraction of ACNO forming the adduct with NBP, as well as the small magnitude of the quotient (k(alk) (ACNO)/k(hyd)(ACNO)) as compared with those reported for other alkylating agents, such as some lactones and N-alkyl-N-nitrosoureas, reveals the ACNO effective alkylating capacity to be less significant; (v) the low value of the NBP-ACNO adduct life (defined as the total amount of adduct present along the progression of the NBP alkylation per unit of alkylating agent concentration) points to the high instability of this adduct; and (vi) the obtained results are in accordance with the low carcinogenicity of ACNO.


Asunto(s)
Acetonitrilos/química , Alquilantes/química , Nitritos/química , Ácido Sórbico/química , Acetonitrilos/toxicidad , Alquilantes/toxicidad , Daño del ADN , Cinética , Piridinas/química
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