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1.
Eur J Neurol ; 28(2): 469-478, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32920917

RESUMEN

BACKGROUND AND PURPOSE: Women may receive stroke care less often than men. We examined the contribution of clinical care on sex differences and health-related quality of life (HRQoL) after stroke. METHODS: We included first-ever strokes registered in the Australian Stroke Clinical Registry (2010-2014) with HRQoL assessed between 90 and 180 days after onset (EQ-5D-3L instrument) that were linked to hospital administrative data (up to 2013). Study factors included sociodemographics, comorbidities, walking ability on admission (stroke severity proxy) and clinical care (e.g. stroke unit care). Responses to the EQ-5D-3L were transformed into a total utility value (-0.516 'worse than death' to 1 'best' health). Quantile regression models, adjusted for confounding factors, were used to determine median differences (MD) in utility scores by sex. RESULTS: Approximately 60% (6852/11 418) of stroke survivors had an EQ-5D-3L assessment (median 139 days; 44% female). Compared with men, women were older (median age 77.1 years vs. men 71.2 years) and fewer could walk on admission (37.9% vs. men 46.1%, P < 0.001). Women had lower utility values than men, and the difference was explained by age and stroke severity, but not clinical care [MDadjusted = -0.039, 95% confidence interval: -0.056, -0.021]. Poorer HRQoL was observed in younger men (aged <65 years), particularly those with more comorbidities, and in older women (aged ≥75 years). CONCLUSIONS: Stroke severity and comorbidities contribute to the poorer HRQoL in young men and older women. Further studies are needed to understand age-sex interaction to better inform treatments for different subgroups and ensure evidence-based treatments to reduce the severity of stroke are prioritized.


Asunto(s)
Calidad de Vida , Accidente Cerebrovascular , Anciano , Australia/epidemiología , Femenino , Humanos , Masculino , Sistema de Registros , Caracteres Sexuales , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/terapia , Encuestas y Cuestionarios
2.
Top Stroke Rehabil ; 30(6): 603-609, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-35786371

RESUMEN

BACKGROUND: People with communication disabilities post-stroke have poor quality-of-life. OBJECTIVES: We aimed to explore the association of self-reported communication disabilities with different dimensions of quality-of-life between 90 and 180 days post-stroke. METHODS: Cross-sectional survey data were obtained between 90 and 180 days post-stroke from registrants in the Australian Stroke Clinical Registry recruited from three hospitals in Queensland. The usual follow-up survey included the EQ5D-3L. Responses to the Hospital Anxiety and Depression Scale, and extra questions (e.g. communication disabilities) were also collected. We used χ2 statistics to determine differences. RESULTS: Overall, 244/647 survivors completed the survey. Respondents with communication disabilities (n = 72) more often reported moderate to extreme problems in all EQ5D-3L dimensions, than those without communication disabilities (n = 172): anxiety or depression (74% vs 40%, p < .001), pain or discomfort (58% vs 39%, p = .006), self-care (46% vs 18%, p < .001), usual activities (77% vs 49%, p < .001), and mobility (68% vs 35%, p < .001). Respondents with communication disabilities reported less fatigue (66% vs 89%, p < .001), poorer cognitive skills (thinking) (16% vs 1%, p < .001) and lower social participation (31% vs 6%, p < .001) than those without communication disabilities. CONCLUSIONS: Survivors of stroke with communication disabilities are more negatively impacted across different dimensions of quality-of-life (as reported between 90 and 180 days post-stroke) compared to those without communication disabilities. This highlights the need for timely and on-going comprehensive multidisciplinary person-centered support.


Asunto(s)
Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/psicología , Estudios Transversales , Australia , Calidad de Vida/psicología , Sobrevivientes/psicología
3.
Disabil Rehabil ; 44(13): 3173-3180, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-33336598

RESUMEN

PURPOSE: The aim of this study was to quantify changes in patients' activity levels, location and people present, within one acute stroke unit (ASU) and one inpatient rehabilitation unit (IRU) with respect to change in hospital design. METHODS: A prospective observational study using behavioural mapping. We observed participants from 8 am till 5 pm every 10 minutes across two days and compared participant activity (physical, social and cognitive), location and people present pre and post-transition to new units. Built design, staffing levels and models of care were contrasted. RESULTS: We recruited 73 participants (63% stroke): old-ASU (n = 19); new-ASU (n = 15); old-IRU (n = 19); new-IRU (n = 20). Compared to old, new units had more single rooms, larger floor spaces and higher staffing levels. We found no significant change in participants' activity levels between the old and new ASU. Participants in the new IRU showed increased physical activity (43.4% vs. 54.4%, p = 0.02) but social and cognitive activity remained similar. Participants were more alone (ASU 47.4% vs. 66.7%, p = 0.01; IRU 41.7% vs. 58.3%, p < 0.001), and less often with nursing staff (ASU 17.7% vs. 6.7%, p = 0.04; IRU 18.8% vs. 5.7%, p < 0.001) in new units. CONCLUSION: Hospital design appears to impact on patients' physical activity. Single rooms may increase isolation and reduce interaction with nursing staff.Implications for rehabilitationDesign of new rehabilitation units needs to consider patients' social engagement with family, friends, other patients and staff in addition to privacy and infection control.A change in built design of rehabilitation units should prompt observation of patients' activity levels and engagement with people and available space to ensure optimal use of new environments.Promotion of communal spaces and activities away from the bedroom to encourage social engagement is recommended for patients recovering in rehabilitation facilities.Less time in contact with nursing staff in rehabilitation environments with predominantly single rooms suggests a review of clinical practice and patient safety is warranted.


Asunto(s)
Arquitectura y Construcción de Hospitales , Accidente Cerebrovascular , Ejercicio Físico , Humanos , Pacientes Internos/psicología , Estudios Observacionales como Asunto , Centros de Rehabilitación
4.
Earth Space Sci ; 8(7): e2020EA001634, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34435081

RESUMEN

The ACT-America project is a NASA Earth Venture Suborbital-2 mission designed to study the transport and fluxes of greenhouse gases. The open and freely available ACT-America data sets provide airborne in situ measurements of atmospheric carbon dioxide, methane, trace gases, aerosols, clouds, and meteorological properties, airborne remote sensing measurements of aerosol backscatter, atmospheric boundary layer height and columnar content of atmospheric carbon dioxide, tower-based measurements, and modeled atmospheric mole fractions and regional carbon fluxes of greenhouse gases over the Central and Eastern United States. We conducted 121 research flights during five campaigns in four seasons during 2016-2019 over three regions of the US (Mid-Atlantic, Midwest and South) using two NASA research aircraft (B-200 and C-130). We performed three flight patterns (fair weather, frontal crossings, and OCO-2 underflights) and collected more than 1,140 h of airborne measurements via level-leg flights in the atmospheric boundary layer, lower, and upper free troposphere and vertical profiles spanning these altitudes. We also merged various airborne in situ measurements onto a common standard sampling interval, which brings coherence to the data, creates geolocated data products, and makes it much easier for the users to perform holistic analysis of the ACT-America data products. Here, we report on detailed information of data sets collected, the workflow for data sets including storage and processing of the quality controlled and quality assured harmonized observations, and their archival and formatting for users. Finally, we provide some important information on the dissemination of data products including metadata and highlights of applications of ACT-America data sets.

5.
Clin Exp Immunol ; 155(3): 514-22, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19068103

RESUMEN

Methionine aminopeptidase-2 (MetAP-2) inhibitors have potent anti-angiogenesis activity and are being developed for the treatment of solid tumours. The recently observed specific expression of MetAP-2 in germinal centre B cells suggests that it has a role in regulating B cell function. We have demonstrated a potent MetAP-2-dependent inhibitory effect on the antibody secretion from B cell receptor and CD40 co-stimulated primary human B cells in the presence of interleukin-21. The effect of MetAP-2 inhibition on antibody secretion was due to a block in differentiation of B cells into plasma cells. Immunohistochemical analysis of germinal centres from human, mouse and marmoset spleen showed a similar expression pattern of MetAP-2 in the marmoset and man, whereas mouse spleen showed no detectable expression. In a marmoset, T dependent immunization model, the MetAP-2 inhibitor suppressed an antigen-specific antibody response. Furthermore, histological analysis showed loss of B cells in the spleen and disrupted germinal centre formation. These results provide experimental evidence to support a novel role for MetAP-2 in immunomodulation. These effects of MetAP-2 are mediated by disruption of the germinal centre reaction and a block in the differentiation of B cells into plasma cells.


Asunto(s)
Aminopeptidasas/antagonistas & inhibidores , Linfocitos B/efectos de los fármacos , Compuestos Epoxi/farmacología , Metaloendopeptidasas/antagonistas & inhibidores , Valina/análogos & derivados , Aminopeptidasas/análisis , Animales , Anticuerpos/inmunología , Linfocitos B/citología , Linfocitos B/inmunología , Callithrix , Diferenciación Celular/efectos de los fármacos , Depresión Química , Ensayo de Inmunoadsorción Enzimática/métodos , Centro Germinal/química , Centro Germinal/efectos de los fármacos , Humanos , Inmunoglobulina G/análisis , Inmunohistoquímica , Recuento de Linfocitos , Metaloendopeptidasas/análisis , Ratones , Modelos Animales , Especificidad de la Especie , Bazo/inmunología , Valina/farmacología
6.
Biochim Biophys Acta ; 1320(3): 265-74, 1997 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-9230921

RESUMEN

Transhydrogenase from mitochondrial and bacterial membranes couples proton translocation to hydride transfer between NAD(H) and NADP(H). The enzyme has three domains, of which domains I and III protrude from the membrane. These possess the NAD(H)- and NADP(H)-binding sites, respectively, whereas domain II spans the membrane. In domain I there is a mobile loop which emanates from the surface of the protein, but which closes down upon NAD(H) binding. In this report we show that the NADP(H)-dependent reduction of acetylpyridine adenine dinucleotide by NADH catalysed by Rhodospirillum rubrum transhydrogenase has 'ping-pong' kinetics, confirming that the reaction is cyclic. We then describe the kinetic and thermodynamic properties of mutants of recombinant domain I protein from the R. rubrum enzyme, in which Tyr-235 in the mobile loop has been substituted with Phe or Asn residues (dI.Y235F and dI.Y235N, respectively). (1) Equilibrium dialysis measurements show that dI.Y235F and dI.Y235N bind NADH more weakly than wild-type domain I protein (the Kd increases twofold and fourfold, respectively). (2) Reverse transhydrogenation rates (in steady state) of domain I-depleted membrane vesicles reconstituted with either dI.Y235F or dI.Y235N are inhibited by about 50% and 78%, respectively, relative to those obtained in reconstitutions with wild-type domain I protein. (3) Reverse transhydrogenation rates (in steady state) of mixtures of recombinant domain III protein and either dI.Y235F or dI.Y235N are inhibited only by about 10% and 20%, respectively, relative to those obtained in mixtures with wild-type protein. (4) Forward transhydrogenation rates (in both the complete enzyme and in domain I:III complexes) are inhibited even less by the mutations than the reverse reactions. (5) In contrast with (1), (2) and (3), cyclic transhydrogenation was strongly inhibited in both the reconstituted membrane system and in the recombinant domain I:III complexes (only 7-8% activity remains with dI.Y235F, and only 2-3% with dI.Y235N). It was recently established that, in contrast to forward and reverse transhydrogenation, the cyclic reaction is substantially limited by the rate of hydride transfer. It is therefore concluded that mutations at Tyr-235 in the mobile loop severely disrupt the hydride transfer step in the catalytic reaction of transhydrogenase.


Asunto(s)
Hidrógeno/metabolismo , NADP Transhidrogenasas/química , NADP Transhidrogenasas/metabolismo , Rhodospirillum rubrum/enzimología , Mutación , NAD/análogos & derivados , NAD/metabolismo , NADP/metabolismo , NADP Transhidrogenasas/genética , Oxidación-Reducción , Unión Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Tirosina/química
7.
Biochim Biophys Acta ; 1229(1): 49-58, 1995 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-7703263

RESUMEN

Proton-translocating transhydrogenase was solubilised and purified from membranes of Escherichia coli. Consistent with recent evidence [Hutton, M., Day, J., Bizouarn, T. and Jackson, J.B. (1994) Eur. J. Biochem. 219, 1041-1051], at low pH and salt concentration, the enzyme catalysed rapid reduction of the NAD+ analogue AcPdAD+ by a combination of NADH and NADPH. At saturating concentrations of NADPH, the dependence of the steady-state rate on the concentrations of NADH and AcPdAD+ indicated that, with respect to these two nucleotides, the reaction proceeds by a ping-pong mechanism. High concentrations of either NADH or AcPdAD+ led to substrate inhibition. These observations support the view that, in this reaction, NADP(H) remains bound to the enzyme: AcPdAD+ is reduced by enzyme-bound NADPH, and NADH is oxidised by enzyme-bound NADP+, in a cyclic process. When this reaction was carried out with [4A-2H]NADH replacing [4A-1H]NADH, the rate was decreased by 46%, suggesting that the H- transfer steps are rate-limiting. In simple 'reverse' transhydrogenation, the reduction of AcPdAD+ was slower with [4B-2H]NADPH than with [4B-1H]NADPH when the reaction was performed at pH 8.0, but there was no deuterium isotope effect at pH 6.0. This indicates that H- transfer is rate-limiting at pH 8.0 and supports our earlier suggestion that NADP+ release from the enzyme is rate-limiting at low pH. The lack of a deuterium isotope effect in the reduction of thio-NADP+ by NADH at low pH is also consistent with the view that NADPH release from the enzyme is slow under these conditions. A steady-state rate equation is derived for the reduction of AcPdAD+ by NADPH plus NADH, assuming operation of the cyclic pathway. It adequately accounts for the pH dependence of the enzyme, for the features described above and for kinetic characteristics of E. coli transhydrogenase described in the literature.


Asunto(s)
Escherichia coli/enzimología , NADP Transhidrogenasas/metabolismo , NADP/metabolismo , Cinética , NAD/análogos & derivados , NAD/metabolismo , NADP Transhidrogenasas/aislamiento & purificación
8.
Biochim Biophys Acta ; 1409(1): 25-38, 1998 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-9804876

RESUMEN

The effects of single amino acid substitutions in the mobile loop region of the recombinant NAD(H)-binding domain (dI) of transhydrogenase have been examined. The mutations lead to clear assignments of well-defined resonances in one-dimensional 1H-NMR spectra. As with the wild-type protein, addition of NADH, or higher concentrations of NAD+, led to broadening and some shifting of the well-defined resonances. With many of the mutant dI proteins more nucleotide was required for these effects than with wild-type protein. Binding constants of the mutant proteins for NADH were determined by equilibrium dialysis and, where possible, by NMR. Generally, amino acid changes in the mobile loop region gave rise to a 2-4-fold increase in the dI-nucleotide dissociation constants, but substitution of Ala236 for Gly had a 10-fold effect. The mutant dI proteins were reconstituted with dI-depleted bacterial membranes with apparent docking affinities that were indistinguishable from that of wild-type protein. In the reconstituted system, most of the mutants were more inhibited in their capacity to perform cyclic transhydrogenation (reduction of acetyl pyridine adenine dinucleotide, AcPdAD+, by NADH in the presence of NADP+) than in either the simple reduction of AcPdAD+ by NADPH, or the light-driven reduction of thio-NADP+ by NADH, which suggests that they are impaired at the hydride transfer step. A cross-peak in the 1H-1H nuclear Overhauser enhancement spectrum of a mixture of wild-type dI and NADH was assigned to an interaction between the A8 proton of the nucleotide and the betaCH3 protons of Ala236. It is proposed that, following nucleotide binding, the mobile loop folds down on to the surface of the dI protein, and that contacts, especially from Tyr235 in a Gly-Tyr-Ala motif with the adenosine moiety of the nucleotide, set the position of the nicotinamide ring of NADH close to that of NADP+ in dIII to effect direct hydride transfer.


Asunto(s)
Sitios de Unión/genética , NADP Transhidrogenasas/química , NAD/metabolismo , Rhodospirillum rubrum/enzimología , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Cinética , Espectroscopía de Resonancia Magnética , Proteínas de la Membrana/química , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida/genética , NADP/metabolismo , NADP Transhidrogenasas/genética , Nucleótidos/metabolismo , Fragmentos de Péptidos/química , Unión Proteica/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
9.
Arch Dermatol ; 128(9): 1201-6, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1519934

RESUMEN

BACKGROUND AND METHODS: Prevalence of benign melanocytic nevi (moles) has been shown to be a major predictor of malignant melanoma. In this study the prevalence of moles in a group of 2140 children, aged 4 to 11 years, was determined. A standard questionnaire was completed by the parents of each child and included information on environmental and life-style factors. Examination data for each child were linked to the data obtained from the questionnaire. RESULTS: Prevalence increases rapidly throughout childhood and studies of children may indicate which factors contribute to mole development. Boys had more moles than girls, as did white children when compared with other ethnic groups. Prevalence of moles increased with age in children of both sexes. Among whites, skin color had little influence on mole prevalence. The following characteristics, however, were associated with an increased prevalence of moles: a propensity to burn rather than tan, a history of sunburn, a tendency to freckle, and a life-style involving increased sun exposure. A striking positive association between prevalence of moles and number of foreign holidays in a hot climate was observed. This association was independent of a history of sunburn. CONCLUSIONS: The study supports the hypothesis that environmental factors influence the prevalence of moles in childhood.


Asunto(s)
Nevo Pigmentado/epidemiología , Neoplasias Cutáneas/epidemiología , Niño , Preescolar , Femenino , Humanos , Masculino , Nevo Pigmentado/etnología , Nevo Pigmentado/etiología , Nevo Pigmentado/patología , Prevalencia , Neoplasias Cutáneas/etnología , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/patología , Quemadura Solar/complicaciones , Reino Unido/epidemiología
10.
Angiology ; 43(1): 11-21, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1532484

RESUMEN

Indium 111-labeled platelet scintigraphy was performed to evaluate platelet deposition in response to different levels of Nd:YAG laser/thermal energy. A dose-related increase in platelet deposition was observed. In clinical studies after laser-assisted balloon angioplasty, intense platelet deposition was observed in 2 patients who subsequently developed clinical arterial thrombosis. The pathogenesis of reocclusion appears, however, to be more complicated and ill understood. The authors suggest further extensive studies incorporating several parameters in the evaluation of the pathogenic factors involved in reocclusion after laser angioplasty. Such studies should also consider the role of arterial injury produced by the balloon catheter after laser-assisted balloon angioplasty.


Asunto(s)
Angioplastia por Láser , Plaquetas/efectos de la radiación , Anciano , Angioplastia de Balón , Plaquetas/diagnóstico por imagen , Femenino , Arteria Femoral/diagnóstico por imagen , Humanos , Técnicas In Vitro , Radioisótopos de Indio , Claudicación Intermitente/sangre , Claudicación Intermitente/diagnóstico por imagen , Claudicación Intermitente/cirugía , Masculino , Persona de Mediana Edad , Arteria Poplítea/diagnóstico por imagen , Complicaciones Posoperatorias/epidemiología , Cintigrafía , Recurrencia , Factores de Tiempo
11.
J R Soc Med ; 80(12): 757-8, 1987 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3430530

RESUMEN

About 10% of all abdominal aortic aneurysms are characterized by an exuberant inflammatory reaction consisting of a dense white sheath over the aneurysm with peri-aortic fibrosis. The aetiology is unknown. There are characteristic ultrasonic and CT appearances but the condition is usually diagnosed at laparotomy. Surgery is the best treatment, keeping peri-aortic dissection to a minimum. Steroid therapy may occasionally be indicated where the situation is considered inoperable or when the patient declines surgery. If hydronephrosis is present because of ureteric involvement, surgical ureterolysis, as for retroperitoneal fibrosis, should be considered. We report 8 cases treated surgically over a 3-year period, with good results in 6, one postoperative amputation and one late postoperative death.


Asunto(s)
Aneurisma de la Aorta/cirugía , Aortitis/cirugía , Anciano , Aorta Abdominal , Humanos , Masculino , Persona de Mediana Edad
12.
J R Soc Med ; 78(6): 440-4, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3999078

RESUMEN

Clinical features and errors in diagnosis have been assessed in a retrospective study of 62 popliteal aneurysms in 40 patients, 22 of whom had bilateral aneurysms. Only 29% of patients complained of pain or swelling behind the knee, while 31% of aneurysms had produced distal ischaemia presenting as intermittent claudication, 9 aneurysms had thrombosed producing ischaemic rest pain in 6 legs, and 4 aneurysms had ruptured. Although 94% of aneurysms were suspected or confidently diagnosed by palpation alone, only 43% of patients had had the correct diagnosis made at the time of initial referral. Treatment was delayed in 12 patients, 8 of whom subsequently required amputation. Popliteal aneurysm should be suspected in patients with a prominent popliteal pulse who present with intermittent claudication, and in patients with acute ischaemia of the leg who may have a thrombosed aneurysm requiring surgical exploration.


Asunto(s)
Aneurisma/diagnóstico , Arteria Poplítea , Adulto , Anciano , Aneurisma/cirugía , Aorta Abdominal , Errores Diagnósticos , Femenino , Arteria Femoral , Humanos , Masculino , Persona de Mediana Edad , Arteria Poplítea/cirugía , Derivación y Consulta , Estudios Retrospectivos
13.
J R Soc Med ; 88(1): 20-3, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7884764

RESUMEN

The operative findings of 23 carotid arteries were compared with pre-operative duplex scans and angiography. Both duplex and angiography had a high degree of accuracy in detecting haemodynamically significant lesions of 50-99% (88 and 92%, respectively). Their accuracy, however, in correctly predicting the grade of stenosis was significantly lower; 30 and 48%, respectively (P < 0.001). They each exhibited an accuracy of 70% and 78%, respectively, in the detection of ulceration. Overall, both duplex and angiography displayed an accuracy of 87% in indicating the proper management course. The combination of both investigations increased this accuracy to 94.6%. In severely stenotic lesions, duplex to rule out occlusion was not reliable. On statistical analysis, there was no difference between duplex and angiography in predicting haemodynamically significant lesions of 50-99%, estimating the grade of stenosis, the detection of ulceration, or indicating the proper management course. In most situations, duplex alone equalled the accuracy of angiography in the pre-operative assessment of patients for carotid surgery. For stenotic lesions of > 90%, however, we recommend supplemental angiography to rule out occlusion.


Asunto(s)
Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/cirugía , Enfermedades de las Arterias Carótidas/cirugía , Estenosis Carotídea/patología , Humanos , Radiografía , Sensibilidad y Especificidad , Ultrasonografía Doppler Dúplex
14.
Int J Stroke ; 7(1): 74-80, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22188854

RESUMEN

BACKGROUND AND HYPOTHESIS: Thrombolytic therapy with tissue plasminogen activator is effective for acute ischaemic stroke within 4·5 h of onset. Patients who wake up with stroke are generally ineligible for stroke thrombolysis. We hypothesized that ischaemic stroke patients with significant penumbral mismatch on either magnetic resonance imaging or computer tomography at three- (or 4·5 depending on local guidelines) to nine-hours from stroke onset, or patients with wake-up stroke within nine-hours from midpoint of sleep duration, would have improved clinical outcomes when given tissue plasminogen activator compared to placebo. STUDY DESIGN: EXtending the time for Thrombolysis in Emergency Neurological Deficits is an investigator-driven, Phase III, randomized, multicentre, double-blind, placebo-controlled study. Ischaemic stroke patients presenting after the three- or 4·5-h treatment window for tissue plasminogen activator and within nine-hours of stroke onset or with wake-up stroke within nine-hours from the midpoint of sleep duration, who fulfil clinical (National Institutes of Health Stroke Score ≥4-26 and prestroke modified Rankin Scale <2) will undergo magnetic resonance imaging or computer tomography. Patients who also meet imaging criteria (infarct core volume <70 ml, perfusion lesion : infarct core mismatch ratio >1·2, and absolute mismatch >10 ml) will be randomized to either tissue plasminogen activator or placebo. STUDY OUTCOME: The primary outcome measure will be modified Rankin Scale 0-1 at day 90. Clinical secondary outcomes include categorical shift in modified Rankin Scale at 90 days, reduction in the National Institutes of Health Stroke Score by 8 or more points or reaching 0-1 at day 90, recurrent stroke, or death. Imaging secondary outcomes will include symptomatic intracranial haemorrhage, reperfusion and or recanalization at 24 h and infarct growth at day 90.


Asunto(s)
Fibrinolíticos/administración & dosificación , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Proyectos de Investigación , Accidente Cerebrovascular/patología , Factores de Tiempo , Tomografía Computarizada por Rayos X
16.
Ann Vasc Surg ; 21(6): 749-53, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17512166

RESUMEN

The incidence of patients presenting with both ruptured abdominal aortic aneurysm (RAAA) and elective abdominal aortic aneurysm (EAAA) increases with age. The aim of our study was to find out the incidence of RAAA, age and sex groups of patients at risk, and 30-day all-cause perioperative mortality associated with RAAA as well as EAAA repair in a busy district general hospital over a 15-year time period. All patients operated for AAA during 1989-2003, both elective and ruptured, were included in the study. Patients who died in the community from RAAA were also included. The data were collected from the hospital information system, theater logbooks, intensive therapy unit records, postmortem register, and patients' medical notes. We divided the data for RAAA into two groups of 7.5 years each to see if there was any improvement over time in 30-day postoperative mortality. There were 816 cases of AAA, which included 468 RAAAs (57%) and 348 EAAAs (43%). Out of 468 RAAAs, 243 patients had emergency repair, of whom 213 were males. There were 201 patients who had RAAA postmortem (43%). Median age (range) was 73 (54-94) years in males and 77 (52-99) years in females, with a male-to-female ratio of 7:1. The peak incidence of RAAA was over 60 years of age in males and 70 years in females. Incidence of RAAA was 7.3/100,000/year in males and 5/100,000/year in females. For RAAA, 30-day perioperative mortality was 43% (105/243) while overall mortality was 70% (330/468), which includes deaths in the community. There was no improvement in 30-day mortality over time after comparing data for the first 7.5 years (50/115, 43.5%) with those for the second set of 7.5 years (55/128, 43%). There were 348 patients who had EAAA repair over the same period, comprising 282 males, with a male:female ratio of 4.3:1. The 30-day mortality in the elective group was 7.75%. Incidence and mortality of RAAA remain high. A high proportion of patients with AAA remain undiagnosed and die in the community. More lives may be saved if a screening program is started for AAA.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Rotura de la Aorta/cirugía , Hospitales Generales/estadística & datos numéricos , Procedimientos Quirúrgicos Vasculares/estadística & datos numéricos , Distribución por Edad , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/diagnóstico , Aneurisma de la Aorta Abdominal/mortalidad , Rotura de la Aorta/diagnóstico , Rotura de la Aorta/mortalidad , Procedimientos Quirúrgicos Electivos/estadística & datos numéricos , Servicios Médicos de Urgencia/estadística & datos numéricos , Inglaterra/epidemiología , Femenino , Humanos , Incidencia , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Estudios Retrospectivos , Distribución por Sexo , Factores de Tiempo , Resultado del Tratamiento
17.
Syst Biol (Stevenage) ; 152(3): 153-60, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16986278

RESUMEN

In previous work, we studied the behaviour of a model of part of the NF-kappaB signalling pathway. The model displayed oscillations that varied both in number, amplitude and frequency when its parameters were varied. Sensitivity analysis showed that just nine of the 64 reaction parameters were mainly responsible for the control of the oscillations when these parameters were varied individually. However, the control of the properties of any complex system is distributed, and, as many of these reactions are highly non-linear, we expect that their interactions will be too. Pairwise modulation of these nine parameters gives a search space some 50 times smaller (81 against 4096) than that required for the pairwise modulation of all 64 reactions, and this permitted their study (which would otherwise have been effectively intractable). Strikingly synergistic effects were observed, in which the effect of one of the parameters was strongly (and even qualitatively) dependent on the values of another parameter. Regions of parameter space could be found in which the amplitude, but not the frequency (timing), of oscillations varied, and vice versa. Such modelling will permit the design and performance of experiments aimed at disentangling the role of the dynamics of oscillations, rather than simply their amplitude, in determining cell fate. Overall, the analyses reveal a level of complexity in these dynamic models that is not apparent from study of their individual parameters alone and point to the value of manipulating multiple elements of complex networks to achieve desired physiological effects.


Asunto(s)
Relojes Biológicos/fisiología , Fenómenos Fisiológicos Celulares , Modelos Biológicos , FN-kappa B/metabolismo , Transducción de Señal/fisiología , Animales , Simulación por Computador , Retroalimentación/fisiología , Regulación de la Expresión Génica/fisiología , Humanos
18.
Haemostasis ; 13(2): 113-8, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6223864

RESUMEN

Coagulation rates in fresh, normal, venous blood was investigated when a given volume of blood was allowed to contact various materials of equivalent surface area, at 22 degrees C, without disturbance. The coagulation rate was determined indirectly by measuring residual thrombin-clottable fibrinogen in cell-free supernatants after arresting coagulation at fixed time intervals with a Ca++-chelating type of anticoagulant and comparing the thrombin-clottable fibrinogen content of the test samples with control samples of blood anticoagulated immediately after venipuncture. In glass containers, after initial formation of the clot, progressive fibrin formation, measured by the rate of disappearance of thrombin-clottable fibrinogen, was found to take place as a gradual and linear progressive process not complete at 30 min after venipuncture with blood stored undisturbed at 22 degrees C. Various graft materials in tubular form were prepared to ensure equivalent blood surface contact. These were investigated for their influence on fibrinogen to fibrin conversion of fresh venous blood in a 15-min period at 22 degrees C. Fibrin formation was greatest in microvel pre-treated with clotting blood and decreased in the following order: microvel, woven Dacron, knitted dacron and Gore-tex. Gore-tex showed by far the least thrombogenicity of all the tested graft materials. We discuss our reasons for making our measurements under non-flow conditions and the reason for measuring fibrinogen to fibrin conversion rather than measuring platelet deposition on the various surfaces.


Asunto(s)
Arterias , Pruebas de Coagulación Sanguínea , Prótesis Vascular/efectos adversos , Fibrina , Vidrio , Polímeros/efectos adversos , Poliestirenos/efectos adversos , Trombosis/inducido químicamente , Femenino , Humanos , Técnicas In Vitro , Masculino , Tereftalatos Polietilenos/efectos adversos , Politetrafluoroetileno/efectos adversos , Factores de Tiempo
19.
Br J Cancer ; 52(5): 765-9, 1985 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-4063150

RESUMEN

Information on exposure and reaction to sunlight, together with the history of exposure to fluorescent lighting, was elicited by postal questionnaire. Case-control analysis from 58 patients with malignant melanoma, 182 matched controls and 151 unmatched controls showed associations between malignant melanoma and (i) bouts of painful sunburn, (ii) reaction of untanned skin to sunlight, and (iii) number of moles (on right forearm), whereas no association could be found with exposure to fluorescent light at work.


Asunto(s)
Luz/efectos adversos , Melanoma/etiología , Neoplasias Cutáneas/etiología , Luz Solar/efectos adversos , Adulto , Anciano , Femenino , Antebrazo , Humanos , Iluminación , Masculino , Persona de Mediana Edad , Nevo Pigmentado/complicaciones , Neoplasias Cutáneas/complicaciones , Quemadura Solar/complicaciones
20.
Postgrad Med J ; 63(744): 903-4, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3447118

RESUMEN

Aneurysms of the iliac arteries usually remain silent, but when they rupture the consequences can be dramatic. They produce few clinical signs suggestive of their presence. However, such aneurysms have been found to be the cause of non-vascular clinical situations. Often they present with features of compression on adjacent viscera. We present a case in which a large common iliac artery aneurysm was found to be causing symptoms of acute sciatic nerve compression.


Asunto(s)
Aneurisma/diagnóstico , Arteria Ilíaca , Síndromes de Compresión Nerviosa/etiología , Nervio Ciático , Enfermedad Aguda , Anciano , Aneurisma/complicaciones , Humanos , Masculino
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