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1.
Cardiol Young ; 34(3): 659-666, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37724575

RESUMEN

BACKGROUND: This meta-analysis aimed to consolidate existing data from randomised controlled trials on hypoplastic left heart syndrome. METHODS: Hypoplastic left heart syndrome specific randomised controlled trials published between January 2005 and September 2021 in MEDLINE, EMBASE, and Cochrane databases were included. Regardless of clinical outcomes, we included all randomised controlled trials about hypoplastic left heart syndrome and categorised them according to their results. Two reviewers independently assessed for eligibility, relevance, and data extraction. The primary outcome was mortality after Norwood surgery. Study quality and heterogeneity were assessed. A random-effects model was used for analysis. RESULTS: Of the 33 included randomised controlled trials, 21 compared right ventricle-to-pulmonary artery shunt and modified Blalock-Taussig-Thomas shunt during the Norwood procedure, and 12 regarded medication, surgical strategy, cardiopulmonary bypass tactics, and ICU management. Survival rates up to 1 year were superior in the right ventricle-to-pulmonary artery shunt group; this difference began to disappear at 3 years and remained unchanged until 6 years. The right ventricle-to-pulmonary artery shunt group had a significantly higher reintervention rate from the interstage to the 6-year follow-up period. Right ventricular function was better in the modified Blalock-Taussig-Thomas shunt group 1-3 years after the Norwood procedure, but its superiority diminished in the 6-year follow-up. Randomised controlled trials regarding medical treatment, surgical strategy during cardiopulmonary bypass, and ICU management yielded insignificant results. CONCLUSIONS: Although right ventricle-to-pulmonary artery shunt appeared to be superior in the early period, the two shunts applied during the Norwood procedure demonstrated comparable long-term prognosis despite high reintervention rates in right ventricle-to-pulmonary artery shunt due to pulmonary artery stenosis. For medical/perioperative management of hypoplastic left heart syndrome, further randomised controlled trials are needed to deliver specific evidence-based recommendations.


Asunto(s)
Procedimiento de Blalock-Taussing , Síndrome del Corazón Izquierdo Hipoplásico , Humanos , Síndrome del Corazón Izquierdo Hipoplásico/cirugía , Puente Cardiopulmonar , Bases de Datos Factuales , Ventrículos Cardíacos/cirugía , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
Phys Rev Lett ; 124(13): 131301, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32302154

RESUMEN

Using only cosmic microwave background polarization data from the polarbear experiment, we measure B-mode polarization delensing on subdegree scales at more than 5σ significance. We achieve a 14% B-mode power variance reduction, the highest to date for internal delensing, and improve this result to 22% by applying for the first time an iterative maximum a posteriori delensing method. Our analysis demonstrates the capability of internal delensing as a means of improving constraints on inflationary models, paving the way for the optimal analysis of next-generation primordial B-mode experiments.

3.
BMC Infect Dis ; 20(1): 186, 2020 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-32111168

RESUMEN

BACKGROUND: The presentation of clinical leptospirosis has been historically associated with animal workers, slaughterhouse workers and medical veterinarians. This association has shifted to be related to flooding events and outdoor activities; few cases are related to high-risk factors found in immunosuppressed patients. Scarcely a handful of cases have serological evidence of immune response against Leptospira serovar Bratislava representing serogroup Australis, a serovar associated with poor reproductive performance in swine and horses, and recently with cats. CASE PRESENTATION: Herein, we describe a rare clinical presentation of disseminated Leptospira infection in an immunosuppressed 65-year-old woman. She was admitted to the emergency room with fever, bacteraemia, bilateral uveitis and pulmonary involvement. The patient denied outdoor activities; she only had wide exposure to faeces and urine from cats living in her home. Her medical history included idiopathic thrombocytopenic purpura (ITP) diagnosed at the age of 18. She did not respond to medical treatment, and a splenectomy was performed. At age 60, she was diagnosed with Chronic Myeloid Leukemia (CML), and was treated with a tyrosine kinase inhibitor (TKI) -Imatinib. The patient voluntarily discontinued the treatment for the last 6 months. After extensive workup, no microorganisms were identified by the commonly used stains in microbiology. The diagnosis was performed through dark-field microscopy, microagglutination test (MAT), Leptospira genus-specific PCR, the IS1500 PCR for identification of pathogenic species, and 16S based sequencing for the genus identification. CONCLUSION: Immunosuppressed patients may acquire uncommon infections from ubiquitous microorganisms. In this case, serology evidence of exposure to Leptospira serovar Bratislava by MAT and the presence of the Leptospira genus were identified. It should be on mind for the diagnosis in otherwise healthy patients, and thoroughly search on splenectomised patients exposed to animals. Additionally, this report highlights the usefulness of PCR for diagnosis of this potentially life-threatening illness.


Asunto(s)
Bacteriemia/diagnóstico , Leptospirosis/diagnóstico , Anciano , Bacteriemia/microbiología , ADN Bacteriano/metabolismo , Femenino , Humanos , Huésped Inmunocomprometido , Leptospira/genética , Leptospira/aislamiento & purificación , Leptospirosis/microbiología , Neumonía por Mycoplasma/diagnóstico , Insuficiencia Respiratoria/diagnóstico , Esplenectomía , Tórax/diagnóstico por imagen , Uveítis/diagnóstico
4.
Clin Radiol ; 73(4): 415.e1-415.e7, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29269038

RESUMEN

AIM: To characterise the meta-analytical functional connectivity patterns in progressive supranuclear palsy (PSP) and compare them to idiopathic Parkinson's disease (IPD). MATERIALS AND METHODS: It was previously reported that PSP and IPD showed distinct regions of brain atrophy based on voxel-based morphometry (VBM) meta-analysis. Using these regions as seeds, healthy control data were referenced to create and statistically compare meta-analytical functional connectivity maps of PSP and IPD. RESULTS: Some overlap was noted between the two diseases, including within the thalamus, striatum, and prefrontal cortex; however, the PSP seeds demonstrated more extensive functional co-activity throughout the brain, particularly within the midbrain, precentral gyrus, parietal cortex, basal ganglia, and cerebellum. CONCLUSION: These findings may help guide future longitudinal studies in the development of new functional imaging biomarkers for diagnosis and assessing treatment response.


Asunto(s)
Mapeo Encefálico/métodos , Imagen por Resonancia Magnética/métodos , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/fisiopatología , Parálisis Supranuclear Progresiva/diagnóstico por imagen , Parálisis Supranuclear Progresiva/fisiopatología , Encéfalo , Humanos
5.
Phys Rev Lett ; 112(13): 131302, 2014 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-24745402

RESUMEN

We reconstruct the gravitational lensing convergence signal from cosmic microwave background (CMB) polarization data taken by the Polarbear experiment and cross-correlate it with cosmic infrared background maps from the Herschel satellite. From the cross spectra, we obtain evidence for gravitational lensing of the CMB polarization at a statistical significance of 4.0σ and indication of the presence of a lensing B-mode signal at a significance of 2.3σ. We demonstrate that our results are not biased by instrumental and astrophysical systematic errors by performing null tests, checks with simulated and real data, and analytical calculations. This measurement of polarization lensing, made via the robust cross-correlation channel, not only reinforces POLARBEAR auto-correlation measurements, but also represents one of the early steps towards establishing CMB polarization lensing as a powerful new probe of cosmology and astrophysics.

6.
Phys Rev Lett ; 113(2): 021301, 2014 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-25062161

RESUMEN

Gravitational lensing due to the large-scale distribution of matter in the cosmos distorts the primordial cosmic microwave background (CMB) and thereby induces new, small-scale B-mode polarization. This signal carries detailed information about the distribution of all the gravitating matter between the observer and CMB last scattering surface. We report the first direct evidence for polarization lensing based on purely CMB information, from using the four-point correlations of even- and odd-parity E- and B-mode polarization mapped over ∼30 square degrees of the sky measured by the POLARBEAR experiment. These data were analyzed using a blind analysis framework and checked for spurious systematic contamination using null tests and simulations. Evidence for the signal of polarization lensing and lensing B modes is found at 4.2σ (stat+sys) significance. The amplitude of matter fluctuations is measured with a precision of 27%, and is found to be consistent with the Lambda cold dark matter cosmological model. This measurement demonstrates a new technique, capable of mapping all gravitating matter in the Universe, sensitive to the sum of neutrino masses, and essential for cleaning the lensing B-mode signal in searches for primordial gravitational waves.

7.
Ecotoxicology ; 23(10): 2005-13, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25185785

RESUMEN

A multi-residue analysis method was developed for the determination of penicillins in wastewater of WWTP, surface water and groundwater in Spain. The procedure involves a solid phase extraction (SPE) and the subsequent analysis by liquid chromatography coupled to tandem mass spectrometry detection (LC-QqQ-MS/MS). The SPE processes were optimized by test of cartridges, sample pH and elution solvents. ENV+ cartridge was chosen for the extraction of penicillins from different environmental samples. The best conditions for the extraction efficiency of the targets were observed at sample pH 6, by eluting solvents of methanol and acetonitrile respectively. The method has been validated by calibration curve, corresponding regression coefficient, limit of quantification and recoveries. The results showed that the recoveries of more than 90% were presented in all the compounds, except AMOX and AMPI, which had special amino-group in the molecular structure different with others. The matrix effect was also considered in the experiment and it was concluded that different matrix effect could be found between three kinds of waters, and the low retention of AMOX and AMPI on the cartridges was attributed to the matrices interference. The real sample detection showed that the penicillins degraded fast and only AMOX appeared in the studied environmental samples. The results of toxicology test on two compounds (AMOX and AMPI) showed that bacteria V. fischeri was proved to be relatively insensitive to both targets. The decreasing order of toxicity in three environmental waters for AMOX and AMPI was: wastewater > groundwater > surface water.


Asunto(s)
Monitoreo del Ambiente/métodos , Penicilinas/análisis , Contaminantes Químicos del Agua/análisis , Cromatografía Liquida , Agua Dulce/química , Agua Subterránea/química , Penicilinas/toxicidad , Extracción en Fase Sólida , España , Espectrometría de Masas en Tándem , Aguas Residuales/química , Contaminantes Químicos del Agua/toxicidad
8.
Phys Med Biol ; 67(12)2022 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-35623349

RESUMEN

Coronary microperfusion assessment is a key parameter for understanding cardiac function. Currently, coronary ultrafast Doppler angiography is the only non-invasive clinical imaging technique able to assess coronary microcirculation quantitatively in humans. In this study, we propose to use fractional moving blood volume (FMBV), proportional to the red blood cell concentration, as a metric for perfusion. FMBV compares the power Doppler in a region of interest (ROI) inside the myocardium to the power Doppler of a reference area in the heart chamber, fully filled with blood. This normalization gives then relative values of the ROI blood filling. However, due to the impact of ultrasound attenuation and elevation focus on power Doppler values, the reference area and the ROI need to be at the same depth to allow this normalization. This condition is rarely satisfiedin vivodue to the cardiac anatomy. Hereby, we propose to locally compensate the attenuation between the ROI and the reference, by measuring the attenuation law on a phantom. We quantified the efficiency of this approach by comparing FMBV with and without compensation on a flow phantom. Compensated FMBV was able to estimate the ground-truth FMBV with less than 5% variation. This method was then adapted to thein vivocase of myocardial perfusion imaging during heart surgery on human neonates. The translation fromin vitrotoin vivorequired an additional clutter filtering step to ensure that blood signals could be correctly identified in the fast-moving myocardium. We applied the singular value decomposition filter on temporal sliding windows whose lengths were a function of myocardium motion. This motion-adaptive temporal sliding window approach was able to improve blood and tissue separation in terms of contrast-to-noise ratio, as compared to well-established constant-length sliding window approaches. Therefore, compensated FMBV and singular value decomposition assisted with motion-adaptive temporal sliding windows improves the quantification of blood volume in coronary ultrafast Doppler angiography.


Asunto(s)
Volumen Sanguíneo , Ultrasonografía Doppler , Velocidad del Flujo Sanguíneo , Angiografía Coronaria , Humanos , Recién Nacido , Fantasmas de Imagen , Ultrasonografía Doppler/métodos
9.
Ann R Coll Surg Engl ; 104(8): 583-587, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35089823

RESUMEN

INTRODUCTION: Low cardiac output following cardiac surgery is a major determinant of outcome that may be improved by early detection, yet there are no widely accepted methods for its measurement in young children. We evaluated the feasibility of the routine use of electrical velocimetry, a non-invasive technique providing continuous measurement of cardiac output, in infants in the early postoperative period. METHODS: With ethical approval and parental consent, infants undergoing cardiac surgery were recruited. The ICON electrical velocimetry monitor was attached on admission to the intensive care unit (ICU) and remained for up to 24h. RESULTS: A total of 15 infants were recruited, median age 3 months (interquartile range (IQR) 0.5-7.5) and weight 4.8kg (IQR 3.9-7.1), undergoing various operations. Cardiac index had a weak correlation with arterial lactate (r=-0.24, p=0.02) and no correlation with blood pressure, central venous pressure or arteriovenous oxygen difference. Data were recorded for a median of 19h (range 5-24), with lead detachment or movement artefact the most common causes of data loss. There was marked minute-to-minute variability, with 25% of consecutive measurements having >5% variability. CONCLUSION: Cardiac index measured by electrical velocimetry in infants in the early postoperative period is impaired by frequent data loss and marked intrapatient variability. Our feasibility study suggests that it is unsuitable for use as a routine monitoring tool in the setting of postsurgical ICU care.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Gasto Cardíaco/fisiología , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Niño , Preescolar , Humanos , Lactante , Monitoreo Fisiológico/métodos , Periodo Posoperatorio , Reología/métodos
10.
Clin Radiol ; 66(8): 778-87, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21570065

RESUMEN

Spondylitis is the most common osseous manifestation of Mycobacterium tuberculosis infection. Although treatable, it continues to cause significant mortality and morbidity. Early diagnosis through familiarity with its imaging characteristics is essential to permit rapid treatment and prevent potential life-limiting consequences. In this review, we demonstrate the key magnetic resonance imaging features of this disease.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Espondilitis/diagnóstico , Tuberculosis de la Columna Vertebral/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Radiobiología , Espondilitis/patología , Tuberculosis de la Columna Vertebral/patología
11.
Biomed Chromatogr ; 25(5): 555-69, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20641008

RESUMEN

This paper presents the multiresidue determination of the series of quinolones regulated by the European Union (marbofloxacin, ciprofloxacin, danofloxacin, enrofloxacin, sarafloxacin, difloxacin, oxolinic acid and flumequine) in bovine and porcine plasma using capillary electrophoresis and liquid chromatography with ultraviolet detection (CE-UV, LC-UV), liquid chromatography-mass spectrometry and -tandem mass spectrometry (LC-MS, LC-MS/MS) methods. These procedures involve a sample preparation by solid-phase extraction for clean-up and preconcentration of the analytes before their injection into the separation system. All methods give satisfactory results in terms of linearity, precision, accuracy and limits of quantification. The suitability of the methods to determine quinolones was evaluated by determining the concentration of enrofloxacin and ciprofloxacin in real samples from pig plasma and cow plasma.


Asunto(s)
Cromatografía Liquida/métodos , Residuos de Medicamentos/análisis , Electroforesis Capilar/métodos , Quinolonas/sangre , Animales , Bovinos , Residuos de Medicamentos/química , Unión Europea , Modelos Lineales , Quinolonas/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Extracción en Fase Sólida , Porcinos , Espectrometría de Masas en Tándem
12.
J Intellect Disabil Res ; 55(9): 832-43, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21554465

RESUMEN

BACKGROUND: The use of out-of-area placements to meet the needs of individuals with intellectual disabilities and challenging behaviour has been increasing in the UK. Such placements claim a large proportion of service budget expenditure; therefore, it is important to consider whether they offer the best-quality care. This paper reports on current evidence relating to such placements and uses a scoping review across five London boroughs to illustrate key issues on provider characteristics and aspects of good practice. METHODS: We conducted a literature review to identify papers that describe out-of-area placements and carried out a postal survey of 54 service providers that delivered services to service users from five London boroughs. RESULTS: Individuals with intellectual disability and challenging behaviour are more likely to be placed out-of-area in services of variable quality and a minority may underperform. Our empirical data suggest that the private sector that is the main accommodation provider is most likely to underperform on meeting standards of care. CONCLUSION: Overall, the majority of out-of-area providers appear to supply a good standard of care but there are many factors that continue to hinder the local treatment of individuals who present with challenging behaviour. There is an imperative to identify poorly performing providers as well as exploring ways in which service users, out-of-area, can be supported effectively.


Asunto(s)
Política de Salud , Discapacidad Intelectual/terapia , Trastornos Mentales/terapia , Instituciones Residenciales/normas , Adulto , Inglaterra , Encuestas de Atención de la Salud , Humanos , Discapacidad Intelectual/epidemiología , Trastornos Mentales/epidemiología , Instituciones Residenciales/estadística & datos numéricos
13.
Rev Sci Instrum ; 90(11): 115115, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31779409

RESUMEN

We describe the Fourier Transform Spectrometer (FTS) used for in-field testing of the POLARBEAR receiver, an experiment located in the Atacama Desert of Chile which measures the cosmic microwave background (CMB) polarization. The POLARBEAR-FTS (PB-FTS) is a Martin-Puplett interferometer designed to couple to the Huan Tran Telescope (HTT) on which the POLARBEAR receiver is installed. The PB-FTS measured the spectral response of the POLARBEAR receiver with signal-to-noise ratio >20 for ∼69% of the focal plane detectors due to three features: a high throughput of 15.1 sr cm2, optimized optical coupling to the POLARBEAR optics using a custom designed output parabolic mirror, and a continuously modulated output polarizer. The PB-FTS parabolic mirror is designed to mimic the shape of the 2.5 m-diameter HTT primary reflector, which allows for optimum optical coupling to the POLARBEAR receiver, reducing aberrations and systematics. One polarizing grid is placed at the output of the PB-FTS and modulated via continuous rotation. This modulation allows for decomposition of the signal into different harmonics that can be used to probe potentially pernicious sources of systematic error in a polarization-sensitive instrument. The high throughput and continuous output polarizer modulation features are unique compared to other FTS calibrators used in the CMB field. In-field characterization of the POLARBEAR receiver was accomplished using the PB-FTS in April 2014. We discuss the design, construction, and operation of the PB-FTS and present the spectral characterization of the POLARBEAR receiver. We introduce future applications for the PB-FTS in the next-generation CMB experiment, the Simons Array.

14.
J Chromatogr A ; 1201(1): 1-14, 2008 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-18556006

RESUMEN

The use of liquid chromatography coupled to orthogonal acceleration time-of-flight mass spectrometry (LC-ToF-MS) provides an attractive alternative to liquid chromatography coupled to quadrupole (LC-MS) or triple quadrupole mass spectrometry (LC-MS/MS) in multiresidue analysis. ToF-MS provides accurate mass information and a significantly higher mass resolution than quadrupole analyzers. In this work, the influential parameters in time-of-flight detection using an electrospray ionization (ESI) source were studied using a central composite design to obtain the main effects and their two-factor interactions. The method developed uses LC-ESI-ToF-MS to determine and characterize quinolones regulated by the EU in pig liver samples below the maximum residue limits (MRLs). Linearity, decision limit, detection capability, detection and quantification limits, precision and recoveries were determined and adequate results were obtained, with quantification limits between 1.5 and 6 microg kg(-1) and recoveries higher than 60% for all quinolones. Limits of detection are lower than 2 microg kg(-1). Results obtained using LC-ESI-ToF-MS were compared with those obtained using LC coupled to a quadrupole and to triple quadrupole mass spectrometer. The work described in this paper illustrates the suitability and excellent confirmatory potential of LC-ToF-MS for multiresidue analysis in food samples.


Asunto(s)
Hígado/química , Espectrometría de Masas/métodos , Quinolonas/química , Animales , Cromatografía Liquida/métodos , Análisis de los Alimentos , Extractos Hepáticos/química , Quinolonas/aislamiento & purificación , Sensibilidad y Especificidad , Porcinos
15.
J Med Ethics ; 34(6): 501-6, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18511628

RESUMEN

OBJECTIVES: To explore opinions and attitudes regarding the current information-giving practices in research involving adults with intellectual disabilities. DESIGN: Qualitative focus group study with a purposive sample. SETTING: An intellectual disabilities service within the NHS PARTICIPANTS: A sample of 26 individuals including adults with mild intellectual disability, carers, clinicians, care managers and the charitable sector. RESULTS: Three main themes were identified: process, format, and content. There was agreement that there is a need for improvement in the process and quality of information giving. With regard to the content of information, there was little discrepancy between the study findings and existing guidance. CONCLUSIONS: Information should be presented in different formats and prepared with input from appropriate professions. Additionally the roles of peers, carers and other professionals in the process of information giving should be considered.


Asunto(s)
Ética en Investigación , Consentimiento Informado , Competencia Mental/legislación & jurisprudencia , Educación del Paciente como Asunto/métodos , Personas con Discapacidades Mentales/psicología , Cuidadores , Grupos Focales , Humanos , Londres , Educación del Paciente como Asunto/ética , Personas con Discapacidades Mentales/legislación & jurisprudencia , Investigación Cualitativa , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
17.
J Pharm Biomed Anal ; 45(5): 730-5, 2007 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-17920225

RESUMEN

The method for the determination of biotin by high performance liquid chromatography (HPLC) coupled with coulometric detector is presented here. Chromatographic and detection conditions were tested. A LiChrospher 60RP-select B column (250 mm x 4 mm; 5 microm) and the mobile phase containing 0.24 mol/L aqueous solution of acetic acid and acetonitrile in the ratio 85:15 (v/v) were found as the most suitable. The flow rate was 1 mL/min and the injected volume of the sample was 20 microL. The hydrodynamic voltammogram of biotin was measured and according to obtained data the detection parameters were set--channel I 600 mV, channel II 900 mV, sensitivity 1 microA. The developed method has been validated. The calibration curve is linear in the range 15-3600 ng/mL, correlation coefficient is 0.9998, limits of detection and quantification are 5 and 15 ng/mL, respectively. Recovery of the spiked samples was 98.67% with R.S.D. 0.255% on average. The developed method has been successfully applied for determination of biotin in pharmaceutical preparations.


Asunto(s)
Biotina/análisis , Cromatografía Líquida de Alta Presión/métodos , Electroquímica/métodos , Preparaciones Farmacéuticas/análisis , Tecnología Farmacéutica/métodos , Biotina/química , Estructura Molecular , Preparaciones Farmacéuticas/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta
18.
Orphanet J Rare Dis ; 12(1): 138, 2017 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-28793912

RESUMEN

BACKGROUND: Hypoplastic left heart syndrome (HLHS) covers a spectrum of rare congenital anomalies characterised by a non-apex forming left ventricle and stenosis/atresia of the mitral and aortic valves. Despite many studies, the causes of HLHS remain unclear and there are conflicting views regarding the role of flow, valvar or myocardial abnormalities in its pathogenesis, all of which were proposed prior to the description of the second heart field. Our aim was to re-evaluate the patterns of malformation in HLHS in relation to recognised cardiac progenitor populations, with a view to providing aetiologically useful sub-groupings for genomic studies. RESULTS: We examined 78 hearts previously classified as HLHS, with subtypes based on valve patency, and re-categorised them based on their objective ventricular phenotype. Three distinct subgroups could be identified: slit-like left ventricle (24%); miniaturised left ventricle (6%); and thickened left ventricle with endocardial fibroelastosis (EFE; 70%). Slit-like ventricles were always found in combination with aortic atresia and mitral atresia. Miniaturised left ventricles all had normally formed, though smaller aortic and mitral valves. The remaining group were found to have a range of aortic valve malformations associated with thickened left ventricular walls despite being described as either atresia or stenosis. The degree of myocardial thickening was not correlated to the degree of valvar stenosis. Lineage tracing in mice to investigate the progenitor populations that form the parts of the heart disrupted by HLHS showed that whereas Nkx2-5-Cre labelled myocardial and endothelial cells within the left and right ventricles, Mef2c-AHF-Cre, which labels second heart field-derived cells only, was largely restricted to the endocardium and myocardium of the right ventricle. However, like Nkx2-5-Cre, Mef2c-AHF-Cre lineage cells made a significant contribution to the aortic and mitral valves. In contrast, Wnt1-Cre made a major contribution only to the aortic valve. This suggests that discrete cardiac progenitors might be responsible for the patterns of defects observed in the distinct ventricular sub-groups. CONCLUSIONS: Only the slit-like ventricle grouping was found to map to the current nomenclature: the combination of mitral atresia with aortic atresia. It appears that slit-like and miniature ventricles also form discrete sub-groups. Thus, reclassification of HLHS into subgroups based on ventricular phenotype, might be useful in genetic and developmental studies in investigating the aetiology of this severe malformation syndrome.


Asunto(s)
Fibroelastosis Endocárdica/metabolismo , Fibroelastosis Endocárdica/patología , Cardiopatías Congénitas/metabolismo , Cardiopatías Congénitas/patología , Síndrome del Corazón Izquierdo Hipoplásico/metabolismo , Síndrome del Corazón Izquierdo Hipoplásico/patología , Animales , Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/patología , Proteína Homeótica Nkx-2.5/metabolismo , Inmunohistoquímica , Factores de Transcripción MEF2/metabolismo , Ratones , Válvula Mitral/metabolismo , Válvula Mitral/patología , Miocardio/metabolismo , Miocardio/patología
19.
J Chromatogr A ; 1135(2): 170-8, 2006 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-17027811

RESUMEN

The aim of this work is to established methods for determination of quinolones (ciprofloxacin, danofloxacin, enrofloxacin, difloxacin and flumequine), regulated by European Union, and sarafloxacin in turkey muscle. An experimental design has been applied for the optimization of the factors that influence the extraction of quinolones from turkey muscle in order to determine the experimental conditions for their extraction with high recoveries. Liquid chromatography with ultraviolet detection (LC-UV), liquid chromatography-mass spectrometry (LC-MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS) have been used for the simultaneous quantification of quinolones antibiotics in turkey muscle. The proposed methods have been validated according to the Food Drugs Administration guideline and presents the limit of quantification below the maximum residue limits established by the European Union for quinolones in turkey muscle. The methods developed have been applied to quantification of enrofloxacin and its main metabolite ciprofloxacin in samples of turkey muscle obtained from animals treated with enrofloxacin.


Asunto(s)
Antibacterianos/análisis , Cromatografía Liquida/métodos , Residuos de Medicamentos/análisis , Espectrometría de Masas/métodos , Músculos/química , Quinolonas/análisis , Espectrofotometría Ultravioleta/métodos , Animales , Unión Europea , Guías como Asunto , Estándares de Referencia , Sensibilidad y Especificidad , Pavos
20.
J Chromatogr A ; 1104(1-2): 132-9, 2006 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-16364336

RESUMEN

This paper presents a comparison between liquid chromatography with ultraviolet detection (LC-UV), liquid chromatography-mass spectrometry (LC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods developed for the multiresidue determination of 8 quinolones, around their maximum residue levels (MRLs) in pig muscle. The procedure involves common extraction of the quinolones from the tissues by traditional extraction, a step for clean-up and preconcentration of the analytes by solid-phase extraction (SPE) and a subsequent liquid chromatographic analysis. The methods present satisfactory results of linearity, precision and limits of quantification much lower than the MRLs established by the European Union for quinolones in pig tissues.


Asunto(s)
Antibacterianos/análisis , Cromatografía Liquida/métodos , Residuos de Medicamentos/análisis , Espectrometría de Masas/métodos , Músculos/química , Quinolonas/análisis , Espectrofotometría Ultravioleta/métodos , Animales , Calibración , Estándares de Referencia , Sensibilidad y Especificidad , Porcinos
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