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1.
Nature ; 562(7727): 386-390, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30305732

RESUMEN

Despite considerable efforts over the past decade, only 34 fast radio bursts-intense bursts of radio emission from beyond our Galaxy-have been reported1,2. Attempts to understand the population as a whole have been hindered by the highly heterogeneous nature of the searches, which have been conducted with telescopes of different sensitivities, at a range of radio frequencies, and in environments corrupted by different levels of radio-frequency interference from human activity. Searches have been further complicated by uncertain burst positions and brightnesses-a consequence of the transient nature of the sources and the poor angular resolution of the detecting instruments. The discovery of repeating bursts from one source3, and its subsequent localization4 to a dwarf galaxy at a distance of 3.7 billion light years, confirmed that the population of fast radio bursts is located at cosmological distances. However, the nature of the emission remains elusive. Here we report a well controlled, wide-field radio survey for these bursts. We found 20, none of which repeated during follow-up observations between 185-1,097 hours after the initial detections. The sample includes both the nearest and the most energetic bursts detected so far. The survey demonstrates that there is a relationship between burst dispersion and brightness and that the high-fluence bursts are the nearby analogues of the more distant events found in higher-sensitivity, narrower-field surveys5.

2.
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
3.
Molecules ; 21(7)2016 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-27384551

RESUMEN

Prostate cancer is one of the most common malignant tumors in males and it has become a major worldwide public health problem. This study characterizes the encapsulation of Nor-ß-lapachone (NßL) in poly(d,l-lactide-co-glycolide) (PLGA) microcapsules and evaluates the cytotoxicity of the resulting drug-loaded system against metastatic prostate cancer cells. The microcapsules presented appropriate morphological features and the presence of drug molecules in the microcapsules was confirmed by different methods. Spherical microcapsules with a size range of 1.03 ± 0.46 µm were produced with an encapsulation efficiency of approximately 19%. Classical molecular dynamics calculations provided an estimate of the typical adsorption energies of NßL on PLGA. Finally, the cytotoxic activity of NßL against PC3M human prostate cancer cells was demonstrated to be significantly enhanced when delivered by PLGA microcapsules in comparison with the free drug.


Asunto(s)
Benzofuranos/administración & dosificación , Cápsulas , Preparaciones de Acción Retardada , Portadores de Fármacos , Ácido Láctico , Naftoquinonas/administración & dosificación , Ácido Poliglicólico , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Benzofuranos/química , Cápsulas/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Humanos , Concentración 50 Inhibidora , Ácido Láctico/química , Masculino , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Naftoquinonas/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Neoplasias de la Próstata , Espectrometría Raman
4.
J Neurol Neurosurg Psychiatry ; 86(12): 1319-23, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25589782

RESUMEN

BACKGROUND AND PURPOSE: Controversy exists over the prognostic significance of the affected hemisphere in stroke. We aimed to determine the relationship between laterality of acute intracerebral haemorrhage (ICH) and poor clinical outcomes. METHODS: A subsidiary analysis of the INTERACT Pilot and INTERACT2 studies--randomised controlled trials of patients with spontaneous acute ICH with elevated systolic blood pressure (BP), randomly assigned to intensive (target systolic BP <140 mm Hg) or guideline-based (<180 mm Hg) BP management. Outcomes were the combined and separate end points of death and major disability (modified Rankin scale (mRS) scores of 3-6, 6 and 3-5, respectively) at 90 days. RESULTS: A total of 2708 patients had supratentorial/hemispheric ICH and information on mRS at 90 days. Patients with right hemispheric ICH (1327, 49%) had a higher risk of death at 90 days compared to those with left hemispheric ICH after adjustment for potential confounding variables (OR, 1.77 (95% CI 1.33 to 2.37)). There were no differences between patients with right and left hemispheric ICH regarding the combined end point of death or major disability or major disability in the multivariable-adjusted models (1.07 (0.89 to 1.29) and 0.85 (0.72 to 1.01), respectively). CONCLUSIONS: Right hemispheric lesion was associated with increased risk of death in patients with acute ICH. The laterality of the ICH does not appear to affect the level of disability in survivors. TRIAL REGISTRATION NUMBER: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00226096 and NCT00716079.


Asunto(s)
Hemorragia Cerebral/mortalidad , Lateralidad Funcional , Anciano , Presión Sanguínea/efectos de los fármacos , Causas de Muerte , Hemorragia Cerebral/fisiopatología , Evaluación de la Discapacidad , Determinación de Punto Final , Femenino , Escala de Coma de Glasgow , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Proyectos Piloto , Pronóstico , Sobrevivientes , Resultado del Tratamiento
5.
Acta Neurol Scand ; 130(2): 73-80, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24796345

RESUMEN

The success of acute stroke treatment is first and foremost time-dependent, and the need for improvement in acute stroke management is demonstrated by the fact that only a minority of patients gain access to treatment - in particular, intravenous recombinant tissue plasminogen activator (IV tPA) - within the necessary time window. Standards of acute stroke care vary widely both regionally and nationally; consequently, various healthcare organizations have undertaken initiatives to measure and improve quality of care. To date, most quality measures have been process-based, focusing primarily on metrics of patient care in the acute hospital-based setting (e.g., time to recombinant tPA administration). Therefore, there remains a need for metrics designed to assess how improvements in process translate into patient outcomes. A global forum was convened to share best practice and provide consensus recommendations on core metrics for measuring improvements in access to care and patient outcomes. Recommendations for core metrics of patient outcomes include hospital-based outcomes (e.g., neurological status at 24 h, ambulatory status at discharge) and post-discharge outcomes (e.g., modified Rankin Scale score at 30 and/or 90 days). Recommendations for best practice relating to aspects of people, process, and technology involved in the stroke treatment pathway that may help provide improvements in these core outcome measures are also outlined.


Asunto(s)
Accidente Cerebrovascular/terapia , Determinación de Punto Final , Humanos , Proteínas Recombinantes/administración & dosificación , Activador de Tejido Plasminógeno/administración & dosificación , Resultado del Tratamiento
6.
Eur J Vasc Endovasc Surg ; 40(4): 475-82, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20727794

RESUMEN

OBJECTIVE: Carotid endarterectomy (CEA) guidelines in symptomatic carotid stenosis are based on NASCET and ECST criteria with 70% or greater carotid stenosis as estimated from a catheter angiogram the major indication. This has several problems: (1) lack of reliable correlation between non-invasive imaging and catheter angiography, which has been largely superseded by non-invasive imaging in investigating carotid stenosis; (2) errors inherent in estimating the degree of stenosis from catheter angiography; (3) disregard for the fact that stroke risk also depends on plaque stability, and number of ischaemic events. METHODS: A retrospective review of ischaemic events, imaging results, operative findings, surgical complications and stroke-free follow-up in 31 patients presenting over a 23 year period with TIA/stroke (symptoms lasting > 24 h and/or imaging evidence of infarction) who had 70% or less carotid stenosis (on non-invasive imaging), but nonetheless underwent CEA. RESULTS: Nineteen patients had small strokes, 7 had TIAs and 5 had ocular events; 28 patients had features of unstable plaque on imaging; 19 patients experienced multiple events before CEA. All had haemorrhagic, ruptured plaque at CEA. One patient suffered an intra-operative stroke, only 1 patient suffered a further stroke/TIA (mean follow-up 4.2 years). CONCLUSION: To predict the likelihood of major stroke in symptomatic carotid stenosis and the benefit of CEA, plaque stability and the number of ischaemic events might be as important as an estimate of the degree of stenosis.


Asunto(s)
Estenosis Carotídea/cirugía , Endarterectomía Carotidea/métodos , Adulto , Anciano , Anciano de 80 o más Años , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico , Estenosis Carotídea/fisiopatología , Diagnóstico por Imagen , Femenino , Estudios de Seguimiento , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos , Factores de Riesgo
7.
J Clin Invest ; 107(12): 1555-62, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11413163

RESUMEN

Peripheral human red blood cells (RBCs) are not generally known to become activated and adhesive in response to cell signaling. We show, however, that soluble thrombospondin via integrin-associated protein (IAP; CD47) increases the adhesiveness of sickle RBCs (SS RBCs) by activating signal transduction in the SS RBC. This stimulated adhesion requires occupancy of IAP and shear stress and is mediated by the activation of large G proteins and tyrosine kinases. Reticulocyte-enriched RBCs derived from sickle-cell disease (SCD) patients are most responsive to IAP-induced activation. These studies therefore establish peripheral SS RBCs as signaling cells that respond to a novel synergy between IAP-induced signal transduction and shear stress, suggesting new therapeutic targets in SCD.


Asunto(s)
Anemia de Células Falciformes/sangre , Antígenos CD/metabolismo , Proteínas Portadoras/metabolismo , Eritrocitos Anormales/fisiología , Transducción de Señal , Antígeno CD47 , Adhesión Celular , Células Cultivadas , Inhibidores Enzimáticos/farmacología , Genisteína/farmacología , Humanos , Modelos Biológicos , Oligopéptidos/farmacología , Fosfotirosina/metabolismo , Estilbenos/farmacología , Estrés Fisiológico , Trombospondinas/metabolismo , Trombospondinas/farmacología , Factores de Virulencia de Bordetella/farmacología
8.
Medchemcomm ; 8(10): 1993-2002, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30108718

RESUMEN

In this work, we characterize nor-ß-lapachone-loaded (NßL-loaded) microcapsules prepared using an emulsification/solvent extraction technique. Features such as surface morphology, particle size distribution, zeta potential, optical absorption, Raman and Fourier transform infrared spectra, thermal analysis data, drug encapsulation efficiency, drug release kinetics and in vitro cytotoxicity were studied. Spherical microcapsules with a size of 1.03 ± 0.46 µm were produced with an encapsulation efficiency of approximately 19%. Quantum DFT calculations were also performed to estimate typical interaction energies between a single nor-ß-lapachone molecule and the surface of the microparticles. The NßL-loaded PLGA microcapsules exhibited a pronounced initial burst release. After the in vitro treatment with NßL-loaded microcapsules, a clear phagocytosis of the spheres was observed in a few minutes. The cytotoxic activity against a set of cancer cell lines was investigated.

9.
Rev Sci Instrum ; 87(2): 023511, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26931853

RESUMEN

We describe an experimental method to measure the gate profile of an x-ray framing camera and to determine several important functional parameters: relative gain (between strips), relative gain droop (within each strip), gate propagation velocity, gate width, and actual inter-strip timing. Several of these parameters cannot be measured accurately by any other technique. This method is then used to document cross talk-induced gain variations and artifacts created by radiation that arrives before the framing camera is actively amplifying x-rays. Electromagnetic cross talk can cause relative gains to vary significantly as inter-strip timing is varied. This imposes a stringent requirement for gain calibration. If radiation arrives before a framing camera is triggered, it can cause an artifact that manifests as a high-intensity, spatially varying background signal. We have developed a device that can be added to the framing camera head to prevent these artifacts.

10.
Stroke ; 36(4): 836-40, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15746461

RESUMEN

BACKGROUND AND PURPOSE: In families with > or =2 relatives with intracranial aneurysms (IAs), screening for IAs in asymptomatic first-degree relatives is often recommended. We assessed the long-term psychosocial impact of such screening. METHODS: We identified all persons with IA (screen-positives) and matched them for age and sex with 2 controls without IA (screen-negatives) from hospital-based registers of familial IA. Persons underwent telephone interviews using questionnaires that covered the areas of psychosocial impact of screening, health-related quality of life (HRQoL), and mood. Data were compared between screen-positives and screen-negatives, and with reference populations. RESULTS: Overall, 105 persons from 33 families with IA were included, of whom 35 were screen-positive and 70 were screen-negative. Of the screen-positives, 12 (44%) had reduced their work and 23 (66%) had experienced changes in > or =1 area of independence, self-esteem, future outlook, or personal relationships. In contrast, only 1 (2%) screen-negative person had stopped working and 12 (17%) others had experienced changes in their self-esteem, future outlook, or relationships. Screen-positives had lower HRQoL compared with screen-negatives and the reference population, whereas both screen groups had higher mean depression scores than the reference population. Despite these effects, only 3 persons regretted participating in screening. CONCLUSIONS: Although screening for IA is an important preventative strategy in high-risk individuals, it is associated with considerable psychosocial effects, both positive and negative. Greater awareness of such outcomes, and appropriate intervention where necessary, would appear to be a necessary component of IA screening programs.


Asunto(s)
Aneurisma Intracraneal/diagnóstico , Tamizaje Masivo/métodos , Tamizaje Masivo/psicología , Hemorragia Subaracnoidea/diagnóstico , Hemorragia Subaracnoidea/psicología , Adulto , Anciano , Ansiedad , Consejo , Depresión , Familia , Salud de la Familia , Femenino , Predisposición Genética a la Enfermedad , Humanos , Aneurisma Intracraneal/genética , Aneurisma Intracraneal/psicología , Masculino , Persona de Mediana Edad , Calidad de Vida , Sistema de Registros , Riesgo , Factores de Riesgo , Factores Sexuales , Encuestas y Cuestionarios , Resultado del Tratamiento
11.
J Gen Physiol ; 91(3): 317-33, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2454282

RESUMEN

Charybdotoxin (CTX), a small, basic protein from scorpion venom, strongly inhibits the conduction of K ions through high-conductance, Ca2+-activated K+ channels. The interaction of CTX with Ca2+-activated K+ channels from rat skeletal muscle plasma membranes was studied by inserting single channels into uncharged planar phospholipid bilayers. CTX blocks K+ conduction by binding to the external side of the channel, with an apparent dissociation constant of approximately 10 nM at physiological ionic strength. The dwell-time distributions of both blocked and unblocked states are single-exponential. The toxin association rate varies linearly with the CTX concentration, and the dissociation rate is independent of it. CTX is competent to block both open and closed channels; the association rate is sevenfold faster for the open channel, while the dissociation rate is the same for both channel conformations. Membrane depolarization enhances the CTX dissociation rate e-fold/28 mV; if the channel's open probability is maintained constant as voltage varies, then the toxin association rate is voltage independent. Increasing the external solution ionic strength from 20 to 300 mM (with K+, Na+, or arginine+) reduces the association rate by two orders of magnitude, with little effect on the dissociation rate. We conclude that CTX binding to the Ca2+-activated K+ channel is a bimolecular process, and that the CTX interaction senses both voltage and the channel's conformational state. We further propose that a region of fixed negative charge exists near the channel's CTX-binding site.


Asunto(s)
Calcio/farmacología , Canales Iónicos/efectos de los fármacos , Potasio/metabolismo , Venenos de Escorpión/farmacología , Animales , Membrana Celular/metabolismo , Caribdotoxina , Conductividad Eléctrica , Técnicas In Vitro , Canales Iónicos/metabolismo , Membrana Dobles de Lípidos , Potenciales de la Membrana , Músculos/metabolismo , Concentración Osmolar , Ratas
12.
Stroke ; 32(3): 613-9, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11239176

RESUMEN

BACKGROUND AND PURPOSE: Publications on the temporal pattern of the occurrence of subarachnoid hemorrhage (SAH) have produced conflicting results. Variations between studies may relate to the relatively small numbers of SAH cases analyzed, including those in meta-analyses. METHODS: We identified all cases of SAH from 3 well-designed population-based studies in Australia (Adelaide, Hobart, and Perth) and New Zealand (Auckland) during 3 periods between 1981 and 1997. The diagnosis of SAH was confirmed with CT, cerebral angiography, cerebrospinal fluid analysis, or autopsy in all cases. Information on the time of occurrence of each event was obtained. Risk ratios (RRs) and 95% CIs were calculated using Poisson regression, with age, sex, smoking status, and history of hypertension entered in the model as covariates. RESULTS: A total of 783 cases of SAH were registered. Age- and sex-adjusted RRs of SAH occurrence were highest in the period between 6 AM and 12 MIDNIGHT (RR 3.2, 95% CI 2.4-4.3) and in winter and spring (RR 1.3, 95% CI 1.1-1.5; RR 1.3, 95% CI 1.1-1.5; respectively). No particular pattern of SAH occurrence was observed according to the day of the week. Restriction of the analyses to proved aneurysmal SAH did not substantially change the point estimates. CONCLUSIONS: Circadian and circaseptan (weekly) fluctuations of SAH occurrence in the southern hemisphere are similar to those in the northern hemisphere, but the occurrence of SAH in Australasia exhibits clear seasonal (winter and spring) peaks.


Asunto(s)
Periodicidad , Hemorragia Subaracnoidea/epidemiología , Distribución por Edad , Australia/epidemiología , Ritmo Circadiano , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Oportunidad Relativa , Sistema de Registros/estadística & datos numéricos , Factores de Riesgo , Estaciones del Año , Distribución por Sexo , Hemorragia Subaracnoidea/diagnóstico , Factores de Tiempo
13.
Stroke ; 31(9): 2080-6, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10978033

RESUMEN

BACKGROUND AND PURPOSE: Few community-based studies have examined the long-term survival and prognostic factors for death within 5 years after an acute first-ever stroke. This study aimed to determine the absolute and relative survival and the independent baseline prognostic factors for death over the next 5 years among all individuals and among 30-day survivors after a first-ever stroke in a population of Perth, Western Australia. METHODS: Between February 1989 and August 1990, all individuals with a suspected acute stroke or transient ischemic attack of the brain who were resident in a geographically defined region of Perth, Western Australia, with a population of 138 708 people, were registered prospectively and assessed according to standardized diagnostic criteria. Patients were followed up prospectively at 4 months, 12 months, and 5 years after the index event. RESULTS: Three hundred seventy patients with first-ever stroke were registered, and 362 (98%) were followed up at 5 years, by which time 210 (58%) had died. In the first year after stroke the risk of death was 36.5% (95% CI, 31.5% to 41.4%), which was 10-fold (95% CI, 8.3% to 11.7%) higher than that expected among the general population of the same age and sex. The most common cause of death was the index stroke (64%). Between 1 and 5 years after stroke, the annual risk of death was approximately 10% per year, which was approximately 2-fold greater than expected, and the most common cause of death was cardiovascular disease (41%). The independent baseline factors among 30-day survivors that predicted death over 5 years were intermittent claudication (hazard ratio [HR], 1.9; 95% CI, 1.2 to 2.9), urinary incontinence (HR, 2.0; 95% CI, 1. 3 to 3.0), previous transient ischemic attack (HR, 2.4; 95% CI, 1.4 to 4.1), and prestroke Barthel Index <20/20 (HR, 2.0; 95% CI, 1.2 to 3.2). CONCLUSIONS: One-year survivors of first-ever stroke continue to die over the next 4 years at a rate of approximately 10% per year, which is twice the rate expected among the general population of the same age and sex. The most common cause of death is cardiovascular disease. Long-term survival after stroke may be improved by early, active, and sustained implementation of effective strategies for preventing subsequent cardiovascular events.


Asunto(s)
Accidente Cerebrovascular/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Enfermedades Cardiovasculares/prevención & control , Causas de Muerte , Ética Médica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Examen Neurológico , Pronóstico , Estudios Prospectivos , Riesgo , Factores Sexuales , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/patología , Análisis de Supervivencia
14.
Neurology ; 55(5): 658-62, 2000 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-10980729

RESUMEN

BACKGROUND: There is limited information about the long-term consequences of subarachnoid hemorrhage (SAH). METHODS: Data were obtained from a population-based study of aneurysmal SAH conducted in Australia and New Zealand between 1995 and 1998. The authors report health outcomes for survivors 1 year after the onset of SAH. RESULTS: From a total of 432 first-ever cases of SAH (76% due to confirmed cerebral aneurysm rupture) registered in four cities in Australia and New Zealand, 242 (56%) were alive approximately 1 year later (mean time 1.2 years), with 230 (95%) available for interview. Of those interviewed, 105 (46%) reported an incomplete recovery, with ongoing problems with memory (50%), mood (39%), speech (14%), and self-care (10%). Compared with age- and sex-adjusted Australian population norms, health-related quality of life, as determined by Short Form-36, was significantly lower for cases in the domains of role limitations that result from physical problems. However, there were no patient or disease characteristics that predicted complete recovery from SAH. CONCLUSIONS: A high proportion of long-term survivors of SAH experience ongoing deficits in high level (neuropsychological) functioning. These deficits result in impairment in social roles.


Asunto(s)
Estado de Salud , Hemorragia Subaracnoidea/epidemiología , Hemorragia Subaracnoidea/fisiopatología , Actividades Cotidianas , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Autoevaluación (Psicología) , Factores de Tiempo
15.
J Immunol Methods ; 117(2): 247-55, 1989 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-2921529

RESUMEN

Binding assays with secretory component (SC) were used to detect polymeric IgA antibody to E. coli lipopolysaccharide and to estimate total polymeric IgA in sera from 14 patients with alcoholic liver disease and eight normal controls. Radioiodinated human SC was shown to bind to polymeric IgA and IgM but not to monomeric IgA, secretory IgA or IgG. Serum aliquots (0.5 ml) were totally depleted of IgM using 2 ml anti-IgM affinity columns and the effluent sera were titrated in microtitre plates coated with lipopolysaccharide, the binding of polymeric IgA being detected by adding 10 ng radiolabelled SC. Total polymeric IgA was measured via its capacity to inhibit the binding of 5 ng labelled SC to IgM coated wells, quantitation being achieved by comparison with the inhibition produced by purified polymeric IgA. Total lipopolysaccharide-specific IgA antibody was detected by ELISA in sera from both patients and controls, 1185 +/- 793 and 56 +/- 19 U/100 microliters (mean +/- SD), respectively; but polymeric IgA antibody was detected only in patients' sera (131 +/- 214 U/100 microliters). The concentration of total polymeric IgA was higher in patients' sera than in control sera (488 +/- 333 and less than 120 micrograms/ml respectively).


Asunto(s)
Inmunoglobulina A/análisis , Fragmentos de Inmunoglobulinas/metabolismo , Componente Secretorio/metabolismo , Anticuerpos Antibacterianos/análisis , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoglobulina A/inmunología , Inmunoglobulina M/análisis , Radioisótopos de Yodo , Lipopolisacáridos/inmunología
16.
Environ Mol Mutagen ; 16(4): 238-45, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2253602

RESUMEN

The results of both the Salmonella/microsome mutagenicity assay and high-performance liquid chromatography (HPLC) analysis were used to evaluate the interactions of binary mixtures of benzo(a)pyrene (BAP) and several different polychlorinated aromatic hydrocarbons. Binary mixtures of either 2-nitro-3,7,8-trichlorodibenzo-p-dioxin (2NTCDD) or pentachlorophenol (PCP) with BAP produced synergism, whereas strictly additive effects were observed with mixtures of octa- or hepta-chlorodibenzo-p-dioxin and BAP. At a dose of 50 micrograms per plate, BAP induced 120 total revertants, whereas the binary mixture of BAP and PCP induced 303 total revertants. The binary mixture of BAP at 1 microgram per plate and 2NTCDD at 0.5 microgram per plate induced 261 net revertants, whereas BAP alone induced 42 net revertants. HPLC analysis of the mixtures indicated that preincubation of BAP with 2NTCDD increased the quantity of benzo(a)pyrene-7,8-dihydrodiol, and 9,10-dihydrodiol metabolites detected. The data suggest that nonmutagenic components of a complex mixture may alter the metabolism of promixate mutagens. Thus, in the present study, 2NTCDD appears to have inhibited the detoxication of BAP metabolites.


Asunto(s)
Benzo(a)pireno/toxicidad , Hidrocarburos Clorados/toxicidad , Salmonella typhimurium/genética , Benzo(a)pireno/metabolismo , Cromatografía Líquida de Alta Presión , Hidrocarburos Clorados/metabolismo , Microsomas/metabolismo , Pruebas de Mutagenicidad , Pentaclorofenol/metabolismo , Pentaclorofenol/toxicidad , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/metabolismo , Dibenzodioxinas Policloradas/toxicidad , Salmonella typhimurium/metabolismo
17.
Cochrane Database Syst Rev ; (2): CD003689, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15106212

RESUMEN

BACKGROUND: Abnormal mood is an important consequence of stroke and may affect recovery and outcome. However, depression and anxiety are often not detected or inadequately treated. This may in part be due to doubts about whether anti-depressant treatments commenced early after the onset of stroke will prevent depression and improve outcome. OBJECTIVES: To determine if pharmaceutical or psychological interventions can prevent the onset of depression, including depressive illness and abnormal mood, and improve physical and psychological outcomes, in patients with stroke. SEARCH STRATEGY: We searched the Cochrane Stroke Group trials register (June 2003). In addition we searched the following electronic databases: Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3, 2002), MEDLINE (1966 to September 2002), EMBASE (1980 to September 2002), CINAHL (1982 to September 2002), PsychINFO (1967 to September 2002), Applied Science and Technology Plus (1986 to September 2002), Arts and Humanities Index (1991 to September 2002), Biological Abstracts (1969 to September 2002), General Science Plus (1994 to September 2002), Science Citation Index (1992 to September 2002), Social Sciences Citation Index (1991 to September 2002), and Sociofile (1974 to September 2002). Reference lists from relevant articles and textbooks were searched, and authors of known studies and pharmaceutical companies who manufacture psychotropic medications were contacted. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials comparing different types of pharmaceutical agents (eg selective serotonin reuptake inhibitors) with placebo, or various forms of psychotherapy against standard care (or attention control), in patients with a recent clinical diagnosis of stroke, where the treatment was undertaken with the explicit intention of preventing depression. DATA COLLECTION AND ANALYSIS: The primary analyses focussed on the proportion of patients who met the standard diagnostic criteria for depression applied in the trials at the end of follow-up. Secondary outcomes included depression or mood scores on standard scales, disability or physical function, death, recurrent stroke, and adverse effects. MAIN RESULTS: Twelve trials involving 1245 participants were included in the review. Data were available for nine trials (11 comparisons) involving different pharmaceutical agents, and three trials of psychotherapy. The time from stroke onset to entry ranged from a few hours to six months, but most patients were recruited within one month of acute stroke. The duration of treatments ranged from two weeks to one year. There was no clear effect of pharmacological therapy on the prevention of depression or on other measures. A significant improvement in mood was evident for psychotherapy, but this treatment effect was small and from a single trial. There was no effect on diagnosed depression. REVIEWERS' CONCLUSIONS: This review identified a small but significant effect of psychotherapy on improving mood, but no effect of either pharmacotherapy or psychotherapy on the prevention of depressive illness, disability, or other outcomes. More evidence is therefore required before any recommendations can be made about the routine use of such treatments to improve recovery after stroke.


Asunto(s)
Depresión/prevención & control , Trastorno Depresivo/prevención & control , Accidente Cerebrovascular/psicología , Afecto , Humanos , Psicoterapia , Ensayos Clínicos Controlados Aleatorios como Asunto
18.
Cochrane Database Syst Rev ; (3): CD003437, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15266484

RESUMEN

BACKGROUND: Depressive and anxiety disorders following stroke are often undiagnosed or inadequately treated. This may reflect difficulties with the diagnosis of abnormal mood among older people with stroke-related disability, but may also reflect uncertainty about the effectiveness of such therapies in this setting. OBJECTIVES: To determine whether pharmacological, psychological, or electroconvulsive treatment (ECT) of depression in patients with stroke can improve outcome. SEARCH STRATEGY: The Cochrane Stroke Group Trials Register (last searched June 2003). The Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3, 2002), MEDLINE (1966 to September 2002), EMBASE (1980 to September 2002), CINAHL (1982 to September 2002), PsychINFO (1967 to September 2002), Applied Science and Technology Plus (1986 to September 2002), Arts and Humanities Index (1991 to September 2002), Biological Abstracts (1969 to September 2002), General Science Plus (1994 to September 2002), Science Citation Index (1992 to September 2002), Social Sciences Citation Index (1991 to September 2002), and Sociofile (1974 to September 2002). Reference lists from relevant articles and textbooks were searched, and authors of known studies and pharmaceutical companies who manufacture psychotropic medications were contacted. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials comparing different types of pharmaceutical agents with placebo, or various forms of psychotherapy with standard care (or attention control), in patients with recent, clinically diagnosed, acute stroke, where treatment was explicitly intended of treat depression. DATA COLLECTION AND ANALYSIS: Primary analyses focussed on the prevalence of diagnosable depressive disorder at the end of treatment. Secondary outcomes included depression or mood scores on standard scales, disability or physical function, death, recurrent stroke, and adverse effects. We did not pool the data for summary scores. We performed meta-analysis for only some binary endpoints and data on adverse events. MAIN RESULTS: Nine trials, with 780 participants, were included in the review. Data were available for seven trials of pharmaceutical agents, and two trials of psychotherapy. There were no trials of ECT. The analyses were complicated by the lack of standardised diagnostic and outcome criteria, and differing analytic methods. There was no strong evidence of benefit of either pharmacotherapy or psychotherapy in terms of a complete remission of depression following stroke. There was evidence of a reduction (improvement) in scores on depression rating scales, and an increase in the proportion of participants with anxiety at the end of follow up. REVIEWERS' CONCLUSIONS: This review found no evidence to support the routine use of pharmacotherapeutic or psychotherapeutic treatment for depression after stroke. More research is required before recommendations can be made about the most appropriate management of depression following stroke.


Asunto(s)
Depresión/terapia , Accidente Cerebrovascular/psicología , Antidepresivos/efectos adversos , Antidepresivos/uso terapéutico , Ansiedad/inducido químicamente , Humanos , Psicoterapia , Ensayos Clínicos Controlados Aleatorios como Asunto
19.
Cochrane Database Syst Rev ; (2): CD003690, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15106213

RESUMEN

BACKGROUND: Antidepressants may be useful in the treatment of abnormal crying associated with stroke. OBJECTIVES: To determine whether pharmaceutical treatment reduces the frequency of emotional displays in people who suffer from emotionalism after stroke. SEARCH STRATEGY: We searched the Cochrane Stroke Group Trials Register (last searched June 2003). In addition we searched the following electronic databases: Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3 2002), MEDLINE (1966 to September 2002), EMBASE (1980 to September 2002), CINAHL (1982 to September 2002), PsychINFO (1967 to September 2002), Applied Science and Technology Plus (1986 to September 2002), Arts and Humanities Index (1991 to September 2002), Biological Abstracts (1969 to September 2002), General Science Plus (1994 to September 2002), Science Citation Index (1992 to September 2002), Social Sciences Citation Index (1991 to September 2002), and Sociofile (1974 to September 2002). We searched reference lists from relevant articles and textbooks, and contacted authors of known studies and pharmaceutical companies who manufacture psychotropic medications. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials, comparing psychotropic medication to placebo, in people with stroke and emotionalism (also known as emotional lability or pathological crying and laughing). DATA COLLECTION AND ANALYSIS: Data were obtained on people who no longer met criteria for emotionalism, as defined in studies, and on reduction in frequency of crying at the end of treatment. Data were not pooled because of the multiplicity of definitions and outcome measures. MAIN RESULTS: Five trials involving 103 participants were included. Four trials showed large effects of treatment: 50% reduction in emotionalism, improvements (reduction) in the frequency of compulsive laughter, and lower (better) scores on the Pathological Laughter and Crying scale. The confidence intervals were wide, however, indicating that treatment may have had only a small positive effect, or even a small negative effect (in one trial). Subgroup analysis was not performed due to the multiple methods of assessment of emotionalism within and between trials. Only one study systematically recorded and reported adverse events; no discernible difference was seen between groups. Participants allocated active treatment were more likely to leave early from trials. REVIEWERS' CONCLUSIONS: Antidepressants can reduce the frequency and severity of crying or laughing episodes. The effect do not seem specific to one drug or class of drugs. However, our conclusions must be qualified by several methodological deficiencies in the studies. More reliable data are required before recommendations can be made about the treatment of post-stroke emotionalism.


Asunto(s)
Antidepresivos/uso terapéutico , Llanto/psicología , Risa/psicología , Accidente Cerebrovascular/psicología , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
20.
Environ Pollut ; 68(1-2): 147-59, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-15092199

RESUMEN

The mutagenic potential of two soils amended with a municipal sewage sludge at two application rates was monitored over a 2-year period using Salmonella/microsome mutagenicity assay. Samples were collected from undisturbed monolith lysimeters of Weswood sandy clay (Fluventic Ustochrept) and Padina sandy loam (Grossarenic Paleustalf) amended with dried sewage sludge at 50 and 100 Mg/ha. Soil samples were collected and sequentially extracted with methylene chloride and methanol. The residues from these extracts were tested for mutagenicity at five doses with and without metabolic activation in Salmonella strain TA98. In general, the mutagenic potential of the amended soils of both application rates for the first 8 weeks following sludge application increased and then slowly decreased. The maximum mutagenic response observed in the soil extracts was 222 revertants at a dose of 10 mg of residue. This response was induced by the methanol extract from the Weswood soil collected 56 days after the application of 50 Mg/ha sewage sludge as compared to the 100 Mg/ha application which induced 202 revertants/mg. The mutagenicity of all fractions extracted from the sludge-amended soil at both application rates collected 717 days after application were not appreciably different from extracts from the unamended soils. The data indicate that chemicals that were mutagenic in bacteria persist in the soil and that at the higher application rates, as much as 2 years may be required for the mutagenic potential of the soil to return to background levels.

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