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BACKGROUND: The large extracellular matrix protein SVEP1 mediates cell adhesion via integrin α9ß1. Recent studies have identified an association between a missense variant in SVEP1 and increased risk of coronary artery disease (CAD) in humans and in mice Svep1 deficiency alters the development of atherosclerotic plaques. However how SVEP1 functionally contributes to CAD pathogenesis is not fully understood. Monocyte recruitment and differentiation to macrophages is a key step in the development of atherosclerosis. Here, we investigated the requirement for SVEP1 in this process. METHODS: SVEP1 expression was measured during monocyte-macrophage differentiation in primary monocytes and THP-1 human monocytic cells. SVEP1 knockout THP-1 cell lines and the dual integrin α4ß1/α9ß1 inhibitor, BOP, were utilised to investigate the effect of these proteins in THP-1 cell adhesion, migration and cell spreading assays. Subsequent activation of downstream integrin signalling intermediaries was quantified by western blotting. RESULTS: SVEP1 gene expression increases in monocyte to macrophage differentiation in human primary monocytes and THP-1 cells. Using two SVEP1 knockout THP-1 cells we observed reduction in monocyte adhesion, migration, and cell spreading compared to control cells. Similar results were found with integrin α4ß1/α9ß1 inhibition. We demonstrate reduced activity of Rho and Rac1 in SVEP1 knockout THP-1 cells. CONCLUSIONS: SVEP1 regulates monocyte recruitment and differentiation phenotypes through an integrin α4ß1/α9ß1 dependent mechanism. GENERAL SIGNIFICANCE: These results describe a novel role for SVEP1 in monocyte behaviour relevant to CAD pathophysiology.
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Integrina alfa4beta1 , Monocitos , Humanos , Moléculas de Adhesión Celular/metabolismo , Diferenciación Celular/genética , Integrina alfa4beta1/metabolismo , Macrófagos/metabolismoRESUMEN
PURPOSE: To develop a consensus statement for the prescription of a Powered Wheelchair Standing Device (PWSD) in young people with Duchenne muscular dystrophy (DMD). MATERIALS AND METHODS: An international multidisciplinary panel comprising clinicians and users (young people with DMD) along with their parents was consulted. A literature review was undertaken and a Delphi method was utilised to generate consensus statements. To supplement limited literature, round one of the Delphi process comprised questions consistent with the International Classification of Functioning, Disability and Health model of disability to generate items based on expert opinion and was completed by 38 clinicians and nine users. Thirty-seven participants completed two further rounds rating the importance of each item with a five-point scale. Agreement of 70% or more participants for items indicated consensus. RESULTS: Consensus was reached for 47 of 80 items. Tolerance and comfort in supported standing for at least 10 min, ankle contracture less than 10 degrees and user goals reflecting motivation to use the standing function were agreed as necessary in guiding the decision to trial a PWSD. Evidence of family, therapist and servicing support were also considered critical in enabling continuity of PWSD use. CONCLUSIONS: PWSD is a mobility option that offers choice, control and opportunity for independence. This consensus statement can assist clinicians with decision-making around factors influencing successful implementation and optimisation of PWSD for young people with DMD.Implications for RehabilitationTolerance and comfort in supported standing for at least 10 minutes, ankle contracture limited to less than 10 degrees and the child's goals reflecting motivation to use the standing position were agreed to be necessary considerations in guiding the decision to trial a PWSD.Trialling a PWSD when the child is predicted to lose the ability to walk within a one to two year period was recommended although a PWSD could be suitable for a child who was unable to walk.Evidence of family, therapist and servicing support was considered critical in enabling continuity of PWSD use.
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Contractura , Distrofia Muscular de Duchenne , Silla de Ruedas , Adolescente , Niño , Técnica Delphi , Humanos , Prescripciones , Posición de PieRESUMEN
BACKGROUND: Patients with acute abdominal pathology requiring emergency laparotomy who experience a delay to theatre have an increased risk of morbidity, mortality and complications. The timeline between symptom onset and operation is ill defined with international variance in assessment and management. This systematic review aims to define where delays to surgery occur and assess the evidence for interventions trialled across Europe. METHODS: A systematic review was performed searching MEDLINE and EMBASE databases (1 January 2005 to 6 May 2020). All studies assessing the impact of time to theatre in patients with acute abdominal pathology requiring emergency laparotomy were considered. RESULTS: Sixteen papers, involving 50 653 patients, were included in the analysis. Fifteen unique timepoints were identified in the patient pathway between symptom onset and operation which are classified into four distinct phases. Time from admission to theatre (1-72 hours) and mortality rate (10.6-74.5 per cent) varied greatly between studies. Mean time to surgery was significantly higher in deceased patients compared with that in survivors. Delays were related to imaging, diagnosis, decision making, theatre availability and staffing. Four of five interventional studies showed a reduced mortality rate following introduction of an acute laparotomy pathway. CONCLUSION: Given the heterogeneous nature of the patient population and pathologies, an assessment and management framework from onset of symptoms to operation is proposed. This could be incorporated into mortality prediction and audit tools and assist in the assessment of interventions.
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Hospitalización , Laparotomía , Europa (Continente) , HumanosRESUMEN
Affinity reagents are of central importance for selectively identifying proteins and investigating their interactions. We report on the development and use of cyclic peptides, identified by mRNA display-based RaPID methodology, that are selective for, and tight binders of, the human hypoxia inducible factor prolyl hydroxylases (PHDs) - enzymes crucial in hypoxia sensing. Biophysical analyses reveal the cyclic peptides to bind in a distinct site, away from the enzyme active site pocket, enabling conservation of substrate binding and catalysis. A biotinylated cyclic peptide captures not only the PHDs, but also their primary substrate hypoxia inducible factor HIF1-α. Our work highlights the potential for tight, non-active site binding cyclic peptides to act as promising affinity reagents for studying protein-protein interactions.
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Formaldehyde is produced in cells by enzyme-catalysed demethylation reactions, including those occurring on N-methylated nucleic acids. Formaldehyde reacts with nucleobases to form N-hydroxymethylated adducts that may contribute to its toxicity/carcinogenicity when added exogenously, but the chemistry of these reactions has been incompletely defined. We report NMR studies on the reactions of formaldehyde with canonical/modified nucleobases. The results reveal that hydroxymethyl hemiaminals on endocyclic nitrogens, as observed with thymidine and uridine monophosphates, are faster to form than equivalent hemiaminals on exocyclic nitrogens; however, the exocyclic adducts, as formed with adenine, guanine and cytosine, are more stable in solution. Nucleic acid demethylase (FTO)-catalysed hydroxylation of (6-methyl)adenosine results in (6-hydroxymethyl)adenosine as the major observed product; by contrast no evidence for a stable 3-hydroxymethyl adduct was accrued with FTO-catalysed oxidation of (3-methyl)thymidine. Collectively, our results imply N-hydroxymethyled adducts of nucleic acid bases, formed either by reactions with formaldehyde or via demethylase catalysis, have substantially different stabilities, with some being sufficiently stable to have functional roles in disease or the regulation of nucleic acid/nucleobase activity.
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Formaldehído/química , Nucleósidos/química , Purinas/química , Pirimidinas/química , Espectroscopía de Resonancia Magnética , Metilación , Nucleósidos/análogos & derivados , NucleótidosRESUMEN
There is interest in developing potent, selective, and cell-permeable inhibitors of human ferrous iron and 2-oxoglutarate (2OG) oxygenases for use in functional and target validation studies. The 3-component Betti reaction enables efficient one-step C-7 functionalisation of modified 8-hydroxyquinolines (8HQs) to produce cell-active inhibitors of KDM4 histone demethylases and other 2OG oxygenases; the work exemplifies how a template-based metallo-enzyme inhibitor approach can be used to give biologically active compounds.
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Inhibidores Enzimáticos/farmacología , Oxigenasas/antagonistas & inhibidores , Oxiquinolina/farmacología , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estructura Molecular , Oxigenasas/metabolismo , Oxiquinolina/síntesis química , Oxiquinolina/química , Relación Estructura-ActividadRESUMEN
Practice development (PD) in mental health nursing has been progressing over the last decade; however, the level and impact of PD activity in the field of mental health remains poorly understood outside localized project impact. More specific reporting and comparative analysis of PD outcomes will improve this situation. In response, this paper presents three case scenarios from work taking place in Australia and New Zealand, as working examples of how PD methodologies have been applied within mental health practice settings. Using a comparative framework that captures the contributing assumptions, practices, processes and conditions imperative to effective PD work within a mental health-care context, three case vignettes are reviewed. The critical question driving this paper is 'what mental health-care services does PD offer in terms of transformational change approaches and the promotion of effective workplace cultures?' Conditions considered necessary for successful PD initiatives within mental health contexts are explored such as how PD converges and diverges with mental health-related theories, plus where and how PD activity best integrates with the specific elements associated with mental health-care provision. The findings are further reviewed in line with reports of PD outcomes from other fields of health care.
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Servicios de Salud Mental/normas , Atención Dirigida al Paciente/normas , Práctica Profesional/normas , Enfermería Psiquiátrica/normas , Humanos , Servicios de Salud Mental/organización & administración , Atención Dirigida al Paciente/organización & administración , Práctica Profesional/organización & administración , Enfermería Psiquiátrica/organización & administraciónRESUMEN
The primary objective of this review was to investigate the current evidence base for the use of choice architecture as a means to change eating behaviour in self-service eating settings, hence potentially reduce calorie intake. Twelve databases were searched systematically for experimental studies with predefined choice architecture interventions in the period of June 2011-March 2012. The 12 included studies were grouped according to type of interventions and underwent a narrative synthesis. The evidence indicates that (i) health labelling at point of purchase is associated with healthier food choice, while (ii) manipulating the plate and cutlery size has an inconclusive effect on consumption volume. Finally, (iii) assortment manipulation and (iv) payment option manipulation was associated with healthier food choices. The majority of studies were of very weak quality and future research should emphasize a real-life setting and compare their results with the effect of other more well-established interventions on food behaviour in self-service eating settings.
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Arquitectura y Construcción de Instituciones de Salud , Conducta Alimentaria/psicología , Etiquetado de Alimentos/normas , Servicios de Alimentación/normas , Conducta de Elección , Ingestión de Energía/fisiología , Servicios de Alimentación/organización & administración , Conductas Relacionadas con la Salud , Humanos , Obesidad/prevención & control , Medio SocialRESUMEN
For many years, the development of insulin resistance has been seen as the core defect responsible for the development of Type 2 diabetes. However, despite extensive research, the initial factors responsible for insulin resistance development have not been elucidated. If insulin resistance can be overcome by enhanced insulin secretion, then hyperglycaemia will never develop. Therefore, a ß-cell defect is clearly required for the development of diabetes. There is a wealth of evidence to suggest that disorders in insulin secretion can lead to the development of decreased insulin sensitivity. In this review, we describe the potential initiating defects in Type 2 diabetes, normal pulsatile insulin secretion and the effects that disordered secretion may have on both ß-cell function and hepatic insulin sensitivity. We go on to examine evidence from physiological and epidemiological studies describing ß-cell dysfunction in the development of insulin resistance. Finally, we describe how disordered insulin secretion may cause intracellular insulin resistance and the implications this concept has for diabetes therapy. In summary, disordered insulin secretion may contribute to development of insulin resistance and hence represent an initiating factor in the progression to Type 2 diabetes.
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Diabetes Mellitus Tipo 2/etiología , Resistencia a la Insulina/fisiología , Células Secretoras de Insulina/fisiología , Insulina/metabolismo , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Humanos , Hiperinsulinismo/complicaciones , Hipoglucemiantes/uso terapéutico , Secreción de Insulina , Células Secretoras de Insulina/metabolismoRESUMEN
A breast support conveyor has the potential to improve bird welfare by avoiding the need to invert and suspend broilers by their legs as they move from the point of shackling to entry into the electric waterbath. To evaluate its effect on welfare under commercial conditions, a breast support conveyor was installed under the conventional shackle line of a small poultry processing plant. A structured assessment of the behaviour of the birds indicated a significant decrease in struggling and wing flapping at the point of shackling, on the straight conveyor and at entry into the waterbath. This resulted in a lower prevalence of red wing tips and bruising in the first wing joint. The shackle line and conveyor in this installation, however, passed around a 90° corner, which appeared to cause more disturbance to the birds on the conveyor than to comparable birds suspended from shackles in the traditional manner. The results indicate that a breast support conveyor has the potential to improve bird welfare on straight shackle lines and that, because struggling activity and duration following shackling are reduced, the time between shackling and stunning could also be reduced using this method, further improving bird welfare. Breast support conveyors should not be used when the shackle lines have sharp bends.
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Mataderos/normas , Bienestar del Animal , Pollos/fisiología , Restricción Física/veterinaria , Estrés Fisiológico/fisiología , Animales , Conducta Animal/fisiología , Restricción Física/métodosRESUMEN
AIMS: To assess the changing rate of amputation in patients with diabetes over a 7-year period. METHODS: All patients undergoing lower extremity amputation in Tayside, Scotland between 1 January 2000 and 31 December 2006 were identified. Temporal linkage of cases to the diabetes database was used to ascertain which amputations were in patients with diabetes. RESULTS: The incidence of major amputations fell from 5.1 [95% confidence interval (CI) 3.8-6.4] to 2.9 (95% CI 1.9-3.8) per 1000 patients with diabetes (P < 0.05). There is a clear linear trend in the adjusted incidence of major amputation (P = 0.023 and 0.027 for age- and sex-adjusted, and duration- and sex-adjusted incidences, respectively). The adjusted incidence of total amputations followed decreased linear regression trend over the whole study period when adjusted for age and sex or diabetes duration and sex (P = 0.002). CONCLUSIONS: There has been a significant reduction in the incidence of major lower extremity amputation in patients with diabetes over the 7-year period.
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Amputación Quirúrgica/estadística & datos numéricos , Pie Diabético/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Pie Diabético/epidemiología , Femenino , Pie/cirugía , Humanos , Incidencia , Pierna/cirugía , Masculino , Persona de Mediana Edad , Análisis de Regresión , Estudios Retrospectivos , Factores de Riesgo , Escocia/epidemiologíaRESUMEN
Classification of the Triatominae has become a complex balance between traditional approaches and a wide variety of evolutionary interpretations. On the one hand is the need for a stable classification of practical use for those involved in vector surveillance and control. On the other is the desire to adequately reflect evolutionary theory derived from a range of molecular, cytogenetic and morphometric comparisons, with additional complications raised by current interpretations of the subfamily as a recently derived polyphyletic assemblage. Here we review key aspects of triatomine systematics and evolution, to derive a pragmatic classification that seeks to build on traditional morphological concepts within the context of current evolutionary theories.
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Evolución Biológica , Triatominae/clasificación , Animales , Filogenia , Triatominae/anatomía & histología , Triatominae/genéticaRESUMEN
The behavioral phenotype characteristic of Williams syndrome (WS) is marked by strong interest in social interaction, manifested in attention to human faces, empathy, approach behavior and social disinhibition, often coexisting with generalized anxiety. Despite their heightened social interest, people with WS show deficits in explicit emotion recognition tasks similar to those of people with other developmental disabilities. In the current study we explored whether individuals with WS show distinctive autonomic responsiveness to social-emotional information, using skin conductance response and heart rate measures. Autonomic activation was investigated in response to facial expressions of emotion in adolescents and adults with WS, compared to age-matched normal controls and to age-, IQ- and language-matched individuals with learning or intellectual disabilities (LID). Overall participants with WS were less electrodermally responsive to dynamically presented face stimuli than the age- and IQ-matched LID group, and showed more heart rate deceleration when viewing emotional faces than the controls. These findings, indicating hypoarousal but increased interest in response to the dynamic presentation of facial emotions in WS, are consistent with the behavioral profile of high approachability toward social stimuli in this population.
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Sistema Nervioso Autónomo/fisiopatología , Expresión Facial , Síndrome de Williams/fisiopatología , Síndrome de Williams/psicología , Adolescente , Adulto , Nivel de Alerta/fisiología , Niño , Interpretación Estadística de Datos , Miedo/fisiología , Femenino , Respuesta Galvánica de la Piel/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Discapacidad Intelectual/psicología , Discapacidades para el Aprendizaje/psicología , Masculino , Pruebas Neuropsicológicas , Estimulación Luminosa , Reconocimiento en Psicología/fisiología , Medio Social , Adulto JovenRESUMEN
The Mental Capacity Act 2005 was partially implemented in April 2007. Doctors should be aware of the Act and what implications it has on their clinical practice. This survey looked at the knowledge of physicians and psychiatrists regarding assessing capacity within the Act by means of a questionnaire. The results showed that 100% of physicians and 70% of the psychiatrists answered questions wrongly in the questionnaire. Also, 97% of physicians and 70% of psychiatrists did not have some aspects of knowledge about capacity. Statistically significant differences in responses between physicians and psychiatrists were in relation to their knowledge of the existence and implementation of the Act. Answers were related to active schizophrenia, weighing up pros and cons, and recent assessment of incapability in relation to being by definition incapable. This study shows that psychiatrists do slightly better in answering questions about the Mental Capacity Act 2005 and about capacity when compared with physicians, however both groups could improve their knowledge. With the full implementation of the Act in October 2007, this study shows the urgency and importance of training in the area of capacity for all doctors.
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Competencia Clínica , Competencia Mental/legislación & jurisprudencia , Médicos , Psiquiatría , Humanos , Consentimiento Informado/legislación & jurisprudencia , Encuestas y Cuestionarios , Reino UnidoRESUMEN
Structural and mechanistic studies on the crotonase superfamily (CS) are reviewed with the aim of illustrating how a conserved structural platform can enable catalysis of a very wide range of reactions. Many CS reactions have precedent in the 'carbonyl' chemistry of organic synthesis; they include alkene hydration/isomerization, aryl-halide dehalogenation, (de)carboxylation, CoA ester and peptide hydrolysis, fragmentation of beta-diketones and C-C bond formation, cleavage and oxidation. CS enzymes possess a canonical fold formed from repeated betabetaalpha units that assemble into two approximately perpendicular beta-sheets surrounded by alpha-helices. CS enzymes often, although not exclusively, oligomerize as trimers or dimers of trimers. Two conserved backbone NH groups in CS active sites form an oxyanion 'hole' that can stabilize enolate/oxyanion intermediates. The range and efficiency of known CS-catalyzed reactions coupled to their common structural platforms suggest that CS variants may have widespread utility in biocatalysis.
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Ácidos Carboxílicos/metabolismo , Enoil-CoA Hidratasa/química , Enoil-CoA Hidratasa/metabolismo , Naturaleza , Secuencia de Aminoácidos , Animales , Sitios de Unión , Humanos , Datos de Secuencia Molecular , Estructura Cuaternaria de Proteína , Estructura Secundaria de ProteínaRESUMEN
Thalamo-cortical networks generate specific patterns of oscillations during distinct vigilance states and epilepsy, well characterized by electroencephalography (EEG). Oscillations depend on recurrent synaptic loops, which are controlled by GABAergic transmission. In particular, GABA A receptors containing the alpha3 subunit are expressed predominantly in cortical layer VI and thalamic reticular nucleus (nRT) and regulate the activity and firing pattern of neurons in relay nuclei. Therefore, ablation of these receptors by gene targeting might profoundly affect thalamo-cortical oscillations. Here, we investigated the role of alpha3-GABA A receptors in regulating vigilance states and seizure activity by analyzing chronic EEG recordings in alpha3 subunit-knockout (alpha3-KO) mice. The presence of postsynaptic alpha3-GABA A receptors/gephyrin clusters in the nRT and GABA A-mediated synaptic currents in acute thalamic slices was also examined. EEG spectral analysis showed no difference between genotypes during non rapid-eye movement (NREM) sleep or at waking-NREM sleep transitions. EEG power in the spindle frequency range (10-15 Hz) was significantly lower at NREM-REM sleep transitions in mutant compared with wild-type mice. Enhancement of sleep pressure by 6 h sleep deprivation did not reveal any differences in the regulation of EEG activities between genotypes. Finally, the waking EEG showed a slightly larger power in the 11-13-Hz band in alpha3-KO mice. However, neither behavior nor the waking EEG showed alterations suggestive of absence seizures. Furthermore, alpha3-KO mice did not differ in seizure susceptibility in a model of temporal lobe epilepsy. Strikingly, despite the disruption of postsynaptic gephyrin clusters, whole-cell patch clamp recordings revealed intact inhibitory synaptic transmission in the nRT of alpha3-KO mice. These findings show that the lack of alpha3-GABA(A) receptors is extensively compensated for to preserve the integrity of thalamo-cortical function in physiological and pathophysiological situations.
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Epilepsia/genética , Epilepsia/fisiopatología , Homeostasis/fisiología , Receptores de GABA-A/genética , Receptores de GABA-A/fisiología , Sueño/genética , Sueño/fisiología , Animales , Nivel de Alerta/genética , Nivel de Alerta/fisiología , Proteínas Portadoras/genética , Proteínas Portadoras/fisiología , Interpretación Estadística de Datos , Electrodos Implantados , Electroencefalografía , Electrofisiología , Antagonistas de Aminoácidos Excitadores/farmacología , Técnica del Anticuerpo Fluorescente , Homeostasis/genética , Ácido Kaínico/farmacología , Proteínas de la Membrana/genética , Proteínas de la Membrana/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Actividad Motora/fisiología , Técnicas de Placa-Clamp , Fenotipo , Fases del Sueño/genética , Fases del Sueño/fisiología , Tálamo/fisiologíaRESUMEN
AIMS: To ascertain which perifoveal changes on digital retinal screening in diabetes predict the need for subsequent macular grid or focal laser therapy. METHODS: Between 1 January 2004 and 31 December 2005, all consecutive retinal images where any lesion was within one disc diameter of the fovea were reviewed. Patients were categorized by lesion at screening as having microaneurysm, single blot haemorrhage, multiple blot haemorrhages and exudates or circinate exudates within one disc diameter of the fovea. We compared these retinal images with the findings on slit lamp examination and the related decision for laser photocoagulation. RESULTS: Four hundred and twenty-four retinal images were identified. Of these, 52 were excluded, principally because of an interval between photography and clinic attendance of greater than 120 days, leaving 372 retinal images in the study group (313 patients). No patients with a single blot haemorrhage required immediate laser therapy at ophthalmology review compared with 13 (23%) of those with multiple blot haemorrhages and 36 (16%) of those with exudates or circinate lesions (P < 0.001). Thirty-nine patients with a single blot haemorrhage who did not require laser therapy underwent ongoing follow-up. None of these underwent laser therapy for maculopathy within the study time frame (9 months from initial screening event). CONCLUSIONS: In this study, no patients with a single blot haemorrhage within one disc diameter of the fovea on digital retinal screening required laser treatment.
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Retinopatía Diabética/diagnóstico , Retinopatía Diabética/complicaciones , Métodos Epidemiológicos , Femenino , Humanos , Coagulación con Láser/métodos , Masculino , Persona de Mediana EdadRESUMEN
Live weight, subjective scores of condition and conformation, live animal video image analysis (LVIA), ultrasound and X-ray computed tomography (CT) scanning were used to investigate the best method or combination of methods for predicting carcass and meat quality traits in live Texel and Scottish Blackface lambs. Predictors derived from CT alone accounted for a high proportion of the variance in dissected fat and muscle weight in Texel lambs (adjusted R(2)=â¼0.8), as well as intra-muscular fat content in the loin (â¼0.6), but lower proportions in Blackface lambs (â¼0.7 for fat, 0.4-0.5 for muscle and intra-muscular fat), after adjusting for sire and fixed effects. Adding traits measured by other in vivo methods increased prediction accuracies (adjusted R(2)) by up to 0.26, depending on trait and data set. Shear force and ultimate pH could not be accurately predicted using the traits considered here (adjusted R(2)<0.4). Although the same methods tended to be best for predicting product quality traits between breeds, prediction accuracies differed.
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Phytanic acid (PA) is an epimeric metabolite of the isoprenoid side chain of chlorophyll. Owing to the presence of its epimeric beta-methyl group, PA cannot be metabolized by beta-oxidation. Instead, it is metabolized in peroxisomes via alpha-oxidation to give pristanic acid, which is then oxidized by beta-oxidation. PhyH (phytanoyl-CoA 2-hydroxylase, also known as PAHX), an Fe(II) and 2OG (2-oxoglutarate) oxygenase, catalyses hydroxylation of phytanoyl-CoA. Mutations of PhyH ablate its role in alpha-oxidation, resulting in PA accumulation and ARD (adult Refsum's disease). The structure and function of PhyH is discussed in terms of its clinical importance and unusual selectivity. Most point mutations of PhyH causing ARD cluster in two distinct groups around the Fe(II)- and 2OG-binding sites. Therapaeutic possibilities for the treatment of Refsum's disease involving PhyH are discussed.