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We performed experiments combining three-dimensional x-ray diffraction and x-ray computed tomography to explore the relationship between microstructure and local force and strain during quasistatic granular compaction. We found that initial void space around a grain and contact coordination number before compaction can be used to predict regions vulnerable to above-average local force and strain at later stages of compaction. We also found correlations between void space around a grain and coordination number, and between grain stress and maximum interparticle force, at all stages of compaction. Finally, we observed grains that fracture to have an above-average initial local void space and a below-average initial coordination number. Our findings provide (1) a detailed description of microstructure evolution during quasistatic granular compaction, (2) an approach for identifying regions vulnerable to large values of strain and interparticle force, and (3) methods for identifying regions of a material with large interparticle forces and coordination numbers from measurements of grain stress and local porosity.
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This paper reviews pastoralism in the Horn of Africa region with reference to the basic socio-economics of pastoralism, and the use of mobile livestock production to generate income and food for human consumption. The paper also examines long-term trends in pastoralist areas which, at first sight, appear to be contradictory. The first trend is the growth of a substantial domestic and export trade in livestock and meat across the region, driven largely by supplies from pastoralist areas and local and international demand. This trend indicates robust and responsive livestock production and marketing in pastoralist areas, despite recurrent drought, conflict and weak governance. In contrast, the second trend sees increasing levels of poverty and destitution in pastoralist areas, and continued high levels of human malnutrition. The co-existence of economic growth and increasing poverty in 'high-export' areas is explained by human population growth, drought, and the private control of pastures and water by wealthier producers. All of these factors combine to push poorer producers out of pastoralism. In areas with lower market orientation, other forms of declining land access are often evident, including the appropriation of land for mechanised farming, hydroelectric schemes, and bush encroachment. These changes, plus population growth and drought, also push people out of pastoralism. In all areas, pastoralism will continue to be the main economic activity but, at the same time, increasing numbers of people are seeking other livelihoods.
Cet article consacré au pastoralisme dans la Corne de l'Afrique au regard de ses principales caractéristiques socio-économiques décrit les utilisations du bétail nomade pour générer des revenus et produire des aliments destinés à la consommation humaine. Les auteurs analysent également les tendances à long terme des régions d'élevage pastoral, qui apparaissent à première vue comme étant contradictoires. La première tendance observée dans cette région a trait à la croissance d'un commerce important d'animaux et de viandes destiné aux marchés nationaux et d'exportation, sous l'impulsion conjointe de l'offre émanant des zones d'élevage pastoral et de la demande tant locale qu'internationale. Cette tendance démontre l'existence dans les zones d'élevage pastoral de capacités de production et commerciales robustes et adaptables, en dépit des épisodes récurrents de sécheresse, des conflits sociaux et d'une gouvernance déficiente. En revanche, la deuxième tendance révèle une aggravation croissante de la pauvreté et de la précarité dans les zones d'élevage pastoral, accompagnées d'une malnutrition importante et persistante dans les populations humaines. La coexistence d'une croissance économique et d'une plus grande pauvreté dans des zones à dominante exportatrice s'explique par la croissance démographique, par les sécheresses et par la mainmise des producteurs les plus riches sur les terres de pâture et sur l'eau. Ces facteurs cumulés détournent du pastoralisme les éleveurs les plus pauvres. Dans les régions à vocation exportatrice moins prononcée, le déclin de l'accès aux pâturages prend d'autres formes clairement identifiables, par exemple l'appropriation des terres en vue de leur exploitation mécanisée, la production d'énergie hydraulique ou l'extension de la brousse. Ces changements s'ajoutant à la croissance démographique et à la sécheresse rendent le pastoralisme beaucoup moins attractif pour les individus. Certes, le pastoralisme restera la principale activité économique des régions étudiées mais en même temps, de plus en plus de gens vont s'orienter vers d'autres moyens de subsistance.
Los autores pasan revista al pastoreo en la región del Cuerno de África, haciendo referencia a sus fundamentos socioeconómicos y a la producción de ganado móvil como medio de generar ingresos y alimentos para el consumo humano. Además, señalan la existencia de tendencias a largo plazo en las zonas de pastoreo que, a primera vista, parecen contradictorias. La primera es el auge de un comercio nacional o exportador de ganado y carne de considerables dimensiones en toda la región, impulsado básicamente por los suministros procedentes de las zonas de pastoreo y por la demanda local e internacional. Esta tendencia pone de manifiesto procesos robustos y flexibles de producción y comercialización de ganado en las zonas pastorales, pese a la recurrencia de sequías y conflictos y a la mala gestión de los asuntos públicos. La segunda tendencia, en acusado contraste, pone de manifiesto niveles crecientes de pobreza e indigencia en las zonas de pastoreo y niveles constantemente elevados de malnutrición humana. La concurrencia de crecimiento económico y pobreza en aumento en zonas eminentemente exportadoras se explica por el crecimiento de la población humana, las sequías y el control privado de los pastos y el agua que ejercen los ganaderos más pudientes. Todos estos factores se combinan para expulsar del pastoreo a los productores pobres. En zonas menos orientadas hacia el mercado aparecen a menudo otras causas de acceso decreciente a la tierra, como la apropiación de suelo para la producción agrícola mecanizada, la instalación de centrales hidroeléctricas o el avance de la maleza. Estos cambios, sumados al crecimiento demográfico y a la sequía, también inducen a las personas a dejar el pastoreo. Y aunque este seguirá siendo la principal actividad económica en todas las zonas, cada vez hay más gente que busca otras formas de ganarse la vida.
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Crianza de Animales Domésticos/tendencias , África Oriental , Crianza de Animales Domésticos/economía , Crianza de Animales Domésticos/métodos , Animales , Sequías/economía , Humanos , Mercadotecnía , Crecimiento Demográfico , Áreas de PobrezaRESUMEN
Microbial communities reside in healthy tissues but are often disrupted during disease. Bacterial genomes and proteins are detected in brains from humans, nonhuman primates, rodents and other species in the absence of neurological disease. We investigated the composition and abundance of microbiota in frozen and fixed autopsied brain samples from patients with multiple sclerosis (MS) and age- and sex-matched nonMS patients as controls, using neuropathological, molecular and bioinformatics tools. 16s rRNA sequencing revealed Proteobacteria to be the dominant phylum with restricted diversity in cerebral white matter (WM) from MS compared to nonMS patients. Both clinical groups displayed 1,200-1,400 bacterial genomes/cm3 and low bacterial rRNA:rDNA ratios in WM. RNAseq analyses showed a predominance of Proteobacteria in progressive MS patients' WM, associated with increased inflammatory gene expression, relative to a broader range of bacterial phyla in relapsing-remitting MS patients' WM. Although bacterial peptidoglycan (PGN) and RNA polymerase beta subunit immunoreactivities were observed in all patients, PGN immunodetection was correlated with demyelination and neuroinflammation in MS brains. Principal component analysis revealed that demyelination, PGN and inflammatory gene expression accounted for 86% of the observed variance. Thus, inflammatory demyelination is linked to an organ-specific dysbiosis in MS that could contribute to underlying disease mechanisms.
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Encéfalo/microbiología , Enfermedades Desmielinizantes/microbiología , Disbiosis/microbiología , Esclerosis Múltiple/microbiología , Proteobacteria/aislamiento & purificación , Sustancia Blanca/microbiología , Actinobacteria/clasificación , Actinobacteria/genética , Actinobacteria/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Autopsia , Encéfalo/patología , Estudios de Casos y Controles , Cianobacterias/clasificación , Cianobacterias/genética , Cianobacterias/aislamiento & purificación , ADN Bacteriano/genética , Enfermedades Desmielinizantes/patología , Disbiosis/patología , Femenino , Humanos , Inflamación , Masculino , Microbiota/genética , Persona de Mediana Edad , Esclerosis Múltiple/patología , Análisis de Componente Principal , Proteobacteria/clasificación , Proteobacteria/genética , ARN Ribosómico 16S/genética , Sustancia Blanca/patologíaRESUMEN
Additive manufacturing (AM) is enabling the fabrication of materials with engineered lattice structures at the micron scale. These mesoscopic structures fall between the length scale associated with the organization of atoms and the scale at which macroscopic structures are constructed. Dynamic compression experiments were performed to study the emergence of behavior owing to the lattice periodicity in AM materials on length scales that approach a single unit cell. For the lattice structures, both bend and stretch dominated, elastic deflection of the structure was observed ahead of the compaction of the lattice, while no elastic deformation was observed to precede the compaction in a stochastic, random structure. The material showed lattice characteristics in the elastic response of the material, while the compaction was consistent with a model for compression of porous media. The experimental observations made on arrays of 4 × 4 × 6 lattice unit cells show excellent agreement with elastic wave velocity calculations for an infinite periodic lattice, as determined by Bloch wave analysis, and finite element simulations.
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OBJECTIVE: Gene expression studies often pool tissues from multiple placentas when using animal models of preeclampsia without accounting for the potential confounders of litter origin or pup sex. We aimed to determine whether placental gene expression differs based on sex or litter. METHODS: We examined the differential expression of soluble fms-like tyrosine kinase 1 (Flt-1) using 35 pups from six normal pregnant mice. RESULTS: Expression of sFlt-1 (p = 0.003) was significantly different between litters but not between sexes (p = 0.17). CONCLUSIONS: These findings highlight the importance of adequate sampling from multiple litters in expression studies when using animal models in clinical research.
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Placenta/metabolismo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Animales , Femenino , Expresión Génica , Ratones , Embarazo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/genéticaRESUMEN
BACKGROUND AND PURPOSE: The prevalence of smoking in schizophrenia patients is exceptionally high; it is not known why but many researchers suggest that smoking constitutes a form of self-medication. Among the symptoms of schizophrenia that may be improved by nicotine are cognitive deficits. Hence, we studied the effects of long-term nicotine administration on cognition in a genetic animal model of schizophrenia susceptibility, G72-transgenic (G72Tg) mice. EXPERIMENTAL APPROACH: The effect of long-term nicotine or saline, administered by osmotic minipumps, on different cognitive domains was assessed in G72Tg mice and controls using a battery of behavioural tests. To investigate the mechanism underlying phenotypic differences, quantitative autoradiographic mapping of nACh receptor subtypes was performed in forebrain structures to explore effects of chronic nicotine exposure on nACh receptor density in wild-type (WT) and G72Tg mice. KEY RESULTS: Genotype significantly affected the cognitive effects of chronic nicotine administration. Whereas chronic nicotine disrupted cognitive performance in WT mice, it was effective at restoring impaired prepulse inhibition, working memory and social recognition in G72Tg mice. However, long-term spatial learning was further impaired by nicotine in transgenic animals. In contrast, associative learning was protected by G72-expression against the adverse nicotine effects seen in WT animals. G72-expression did not decisively influence nicotine-induced up-regulation of the α4ß2*subtype, whereas α7nACh receptor density was differentially altered by genotype or by a genotype·treatment interaction in specific brain areas, most notably hippocampal subregions. CONCLUSIONS AND IMPLICATIONS: Our data support the hypothesis that nicotine self-medication of schizophrenics improves cognitive symptoms, possibly by facilitating nicotine-induced α7nACh receptor activation in the hippocampus.
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Conducta Animal/efectos de los fármacos , Memoria a Corto Plazo/efectos de los fármacos , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Nootrópicos/administración & dosificación , Esquizofrenia/tratamiento farmacológico , Psicología del Esquizofrénico , Animales , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Cognición/efectos de los fármacos , Modelos Animales de Enfermedad , Esquema de Medicación , Genotipo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Ratones , Ratones Transgénicos , Inhibición Neural/efectos de los fármacos , Fenotipo , Prosencéfalo/efectos de los fármacos , Prosencéfalo/metabolismo , Reconocimiento en Psicología/efectos de los fármacos , Esquizofrenia/diagnóstico , Esquizofrenia/genética , Conducta Social , Factores de Tiempo , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Receptor Nicotínico de Acetilcolina alfa 7/metabolismoRESUMEN
BACKGROUND: Emergency department (ED) crowding caused by access block is an increasing public health issue and has been associated with impaired healthcare delivery, negative patient outcomes and increased staff workload. AIM: To investigate the impact of opening a new ED on patient and healthcare service outcomes. METHODS: A 24-month time series analysis was employed using deterministically linked data from the ambulance service and three ED and hospital admission databases in Queensland, Australia. RESULTS: Total volume of ED presentations increased 18%, while local population growth increased by 3%. Healthcare service and patient outcomes at the two pre-existing hospitals did not improve. These outcomes included ambulance offload time: (Hospital A PRE: 10 min, POST: 10 min, P < 0.001; Hospital B PRE: 10 min, POST: 15 min, P < 0.001); ED length of stay: (Hospital A PRE: 242 min, POST: 246 min, P < 0.001; Hospital B PRE: 182 min, POST: 210 min, P < 0.001); and access block: (Hospital A PRE: 41%, POST: 46%, P < 0.001; Hospital B PRE: 23%, POST: 40%, P < 0.001). Time series modelling indicated that the effect was worst at the hospital furthest away from the new ED. CONCLUSIONS: An additional ED within the region saw an increase in the total volume of presentations at a rate far greater than local population growth, suggesting it either provided an unmet need or a shifting of activity from one sector to another. Future studies should examine patient decision making regarding reasons for presenting to a new or pre-existing ED. There is an inherent need to take a 'whole of health service area' approach to solve crowding issues.
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Ambulancias , Bases de Datos Factuales/tendencias , Atención a la Salud/tendencias , Servicios Médicos de Urgencia/tendencias , Servicio de Urgencia en Hospital/tendencias , Adolescente , Adulto , Ambulancias/normas , Atención a la Salud/normas , Servicios Médicos de Urgencia/normas , Servicio de Urgencia en Hospital/normas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Carga de Trabajo/normas , Adulto JovenRESUMEN
Humans have genetically based unique abilities making complex culture possible; an assemblage of traits which we term "cultural capacity". The age of this capacity has for long been subject to controversy. We apply phylogenetic principles to date this capacity, integrating evidence from archaeology, genetics, paleoanthropology, and linguistics. We show that cultural capacity is older than the first split in the modern human lineage, and at least 170,000 years old, based on data on hyoid bone morphology, FOXP2 alleles, agreement between genetic and language trees, fire use, burials, and the early appearance of tools comparable to those of modern hunter-gatherers. We cannot exclude that Neanderthals had cultural capacity some 500,000 years ago. A capacity for complex culture, therefore, must have existed before complex culture itself. It may even originated long before. This seeming paradox is resolved by theoretical models suggesting that cultural evolution is exceedingly slow in its initial stages.
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Evolución Cultural , Relaciones Interpersonales , Arqueología/métodos , Evolución Biológica , Linaje de la Célula , Humanos , Lenguaje , FilogeniaRESUMEN
Combination of drugs with different targets is a logical approach to overcome multilevel cross-stimulation among key pathways in NSCLC progression such as EGFR, K-Ras and VEGFR. The sorafenib-erlotinib combination showed clinical activity and acceptable safety. Therefore, we evaluated mechanisms underlying sorafenib-erlotinib interaction in seven NSCLC cell lines selected for their heterogeneous pattern of EGFR and Raf-kinase-inhibitor protein (RKIP) expression, and EGFR/K-Ras mutations. Pharmacologic interaction was studied using MTT/SRB assays and the combination index (CI) method, while effects on EGFR, Erk1/2 and Akt phosphorylation, cell cycle and apoptosis were studied with western-blot, ELISA, and flow cytometry. Intracellular drug concentrations were measured with LC-MS/MS, whereas kinase activity profiles were generated on tyrosine kinase peptide substrate arrays. Synergism was detected in all cell lines, with CIs < 0.6 in K-Ras mutated A549, SW1573 and H460, as well as in H1975 (EGFR-T790M) cells. Sorafenib slowed cell cycle progression and induced apoptosis, which was significantly increased in the combination. Moreover, sorafenib reduced Akt/ERK phosphorylation in erlotinib-resistant cells, associated with significant RKIP up-regulation. No direct drug interaction was detected by LC-MS/MS measurement, while lysates from A549 and H1975 cells exposed to erlotinib+sorafenib showed a significant inhibition in the phosphorylation of 16 overlapping peptides, including sites from RAF, VEGFR2, PDGFR, CDK2 and SRC, suggesting new markers to identify NSCLC patients who are likely to respond to this treatment. In conclusion, several mechanisms, including apoptosis-induction, modulation of expression/phosphorylation of RKIP and crucial kinases contribute to erlotinib-sorafenib synergistic interaction and should be evaluated in future trials for the rational development of this combination in NSCLC.
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Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Niacinamida/análogos & derivados , Compuestos de Fenilurea/farmacología , Quinazolinas/farmacología , Apoptosis/efectos de los fármacos , Western Blotting , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Cromatografía Liquida , Sinergismo Farmacológico , Ensayo de Inmunoadsorción Enzimática , Clorhidrato de Erlotinib , Citometría de Flujo , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Terapia Molecular Dirigida , Niacinamida/administración & dosificación , Niacinamida/farmacología , Compuestos de Fenilurea/administración & dosificación , Proteínas de Unión a Fosfatidiletanolamina , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/administración & dosificación , Sorafenib , Espectrometría de Masas en TándemRESUMEN
BACKGROUND: The serum proteomic test VeriStrat has been shown to be able to classify advanced non-small cell lung cancer (NSCLC) patients for overall survival (OS) after treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). In this study, VeriStrat was evaluated as a pre-treatment stratification tool in patients with advanced stage NSCLC for treatment with the combination of erlotinib and sorafenib, considering both OS and progression-free survival (PFS) as end points. METHODS: Serum samples from 50 patients treated within the context of a phase II trial of first-line erlotinib and sorafenib were analysed with VeriStrat, a fully locked mass spectrometry-based test that identifies patients likely to have good or poor outcome on EGFR therapy based on eight distinct features in mass spectra. Analysis was performed fully blinded to all clinical data, and then the outcome data were analysed with respect to the obtained serum classifications. RESULTS: VeriStrat classified pre-treatment samples into two groups, VeriStrat Good and VeriStrat Poor, which were significantly different in OS (hazard ratio (HR) 0.30, log-rank P=0.009) and in PFS (HR 0.40, log-rank P=0.035). CONCLUSION: VeriStrat has shown its potential for stratification of unselected, advanced stage NSCLC patients treated in first line with a combination of erlotinib and sorafenib.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/antagonistas & inhibidores , Neoplasias Pulmonares/tratamiento farmacológico , Niacinamida/análogos & derivados , Compuestos de Fenilurea/administración & dosificación , Inhibidores de Proteínas Quinasas/administración & dosificación , Quinazolinas/administración & dosificación , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Supervivencia sin Enfermedad , Clorhidrato de Erlotinib , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Estadificación de Neoplasias , Niacinamida/administración & dosificación , Pronóstico , SorafenibRESUMEN
PURPOSE: Transcranial color-coded sonography (TCCS) and CT-angiography (CTA) are reliable tools for detection of intracranial stenosis. Current ultrasonographic criteria for middle cerebral artery (MCA) stenosis are usually limited to a dichotomized grading (< or ≥â50â%). As for carotid arteries, continuity equation might provide a more accurate evaluation of degree of MCA stenosis. We aimed to apply continuity equation to calculate degree of MCA stenosis with TCCS and to compare these results with CTA. MATERIALS AND METHODS: All patients admitted to our Neurovascular Center with ischemic stroke or TIA underwent TCCS examination. Degree of MCA stenosis was calculated based on continuity equation as (1â-â[PSVprestenotic/PSVintrastenotic]â×â100)â%. CTA was performed when TCCS detected MCA stenosis, and degree of stenosis was calculated by diameter (D) as: (1â-â[Dprestenotic/Dintrastenotic]â×â100)â%. Correlation between TCCS and CTA results was tested. Continuity equation method was compared to cut-off velocity method for detection of ≥â50â% MCA stenosis. To assess TCCS inter-observer agreement, evaluation of MCA stenosis was repeated by another neurosonographer in a subgroup of patients. RESULTS: The overall correlation coefficient between TCCS and CTA was 0.85 (pâ<â0.0001). Correlation coefficient for stenosis defined with CTA as ≥â50â% was 0.94 (pâ<â0.0001). TCCS inter-observer agreement on degree of stenosis was 0.85 (pâ=â0.001). In detection of ≥â50â% MCA stenosis, continuity equation method showed a sensitivity of 78â% (14/18) and a specificity of 86â% (19/22), while the cut-off velocity method showed a sensitivity of 67â% (12/18) and a specificity of 86â% (19/22). CONCLUSION: This study shows that ultrasonographic evaluation of MCA stenosis applying the continuity equation provides reproducible and accurate results, and is more sensitive in detection of ≥â50â% MCA stenosis than cut-off velocity method.
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Angiografía Cerebral/métodos , Interpretación de Imagen Asistida por Computador/métodos , Infarto de la Arteria Cerebral Media/diagnóstico , Cómputos Matemáticos , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía Doppler en Color/métodos , Ultrasonografía Doppler Transcraneal/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadística como AsuntoRESUMEN
INTRODUCTION: Visualisation of the microcirculation through retinal imaging can provide information on the health of systemic vasculature. Characterisation of the retinal vasculature throughout pregnancy using retinal imaging is a novel approach to examine physiological changes to the cardiovascular system, and may be useful to predict early pathophysiological signs of adverse maternal outcomes. OBJECTIVES: To characterise the retinal vascular and blood pressure (BP) changes that occur throughout a healthy pregnancy. METHODS: Data was collected from women recruited at 13±2 weeks of gestation from Royal Prince Alfred Hospital, a major tertiary referral hospital in Sydney, Australia. Retinal images centred on the optic disc and BP readings were collected throughout pregnancy. Postnatal data was collected from medical records, and women with hypertensive disorders of pregnancy and gestational diabetes mellitus were excluded. This left a final group of 19 women. Retinal images from 13±2, 19±2, 29±2 and 38±2 weeks gestation were graded using semi-automated retinal vascular calibre measurement (IVAN) software and the central retinal arteriolar equivalent (CRAE), and central retinal venular equivalent (CRVE). BP data was collected at the same time points as the retinal images. Analysis of data was performed using paired t-tests and repeated measures analysis of variance (ANOVA). Women with missing data points were excluded from the analysis at the relevant time points. RESULTS: Over the course of pregnancy, there was a significant dilatation of retinal arterioles between 13±2 and 19±2weeks (from 166.4 to 172.7µm, SE: 3.7µm, n=19, p=0.01), corresponding to a significant fall in diastolic BP during this time (from 64.6 to 60.2mmHg, SE: 1.5mmHg, p=0.01). No significant changes in venular diameter or systolic BP were noted. Between 19±2 and 29±2weeks (n=4), no significant changes to retinal arteriolar or venular diameter were seen although there were significant increases in both systolic and diastolic BP (SBP: from 100.3 to 109.9mmHg, SE: 1.9mmHg, p=0.01; DBP: from 59.3 to 64.6mmHg, SE: 6.9mmHg, p=0.01). Between 29±2 and 38±2weeks (n=3), no significant changes in retinal arteriolar, and venular diameter or BP were observed. CONCLUSION: An increase in retinal arteriolar diameter between 13±2 and 19±2 weeks gestation was observed, which corresponded to a decrease in both systolic and diastolic BP. However, between 19±2 and 29±2 weeks there was no change in vasculature, even though there was a significant increase in BP. By characterising the changes to retinal vessels that occur throughout a healthy pregnancy, we can further our understanding of the response of the systemic vasculature to pregnancy, which may provide clues to early vascular disease of pregnancies.
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INTRODUCTION: Hypertensive disorders of pregnancy (HDP) are characterised by vascular dysfunction. Retinal vascular imaging is a novel, non-invasive way to characterise early microvascular changes in pregnancy, and as a result has the potential to be used to predict the onset of HDP. OBJECTIVES: To characterise retinal vascular changes that occur in HDP, and compare these changes to those in healthy pregnancies. METHODS: Women were recruited at 13±2 weeks of gestation from Royal Prince Alfred Hospital, a major metropolitan tertiary referral hospital in Sydney, Australia. Retinal images centred on the optic disc and blood pressure (BP) readings were collected at 13±2, 19±2, 29±2 and 38±2 weeks gestation. Retinal images were graded using semi-automated retinal vascular calibre measurement software (IVAN) and the central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were calculated. Within and between subject repeat measures analysis was performed on images from each trimester, using paired t-tests and repeated measures analysis of variance (ANOVA). Multiple linear regressions were used to model the average arteriole diameter adjusted for age, tobacco consumption and body mass index (BMI). All tests were two-sided using a 5% level of significance. A clinical diagnosis of HDP was obtained from postnatal medical record data. Women with missing data points were excluded from the analysis at that time point. RESULTS: Of the 39 women included in the study, 6 (15%) were diagnosed with HDP. In the HDP cohort, repeated measures ANOVA revealed no significant changes in arteriolar or venular diameter measurements throughout pregnancy. Paired t-tests indicated no significant differences in any of the outcome measures between HDP and healthy pregnancies at 13±2 (n=36) and 19±2 (n=39)weeks. At 29±2weeks (n=39), there was a significantly smaller venular diameter in HDP pregnancies (220.4±6.9µm vs 239.1± 5.4µm in healthy pregnancies, p=0.03). At 38±2weeks (n=39), arteriolar diameter was significantly smaller in HDP pregnancies (148.6±6.0µm vs 164.1±4.6µm in healthy pregnancies, p=0.04). Similar results persisted following adjustments for cardiovascular risk factors (age, tobacco use and BMI). CONCLUSION: Significant differences in the retinal vasculature develop in HDP as compared to healthy pregnancies. These differences appear at29±2weeks gestation and persist throughout the rest of the pregnancy. Retinal vascular imaging is a promising tool for the detection of the early microvascular changes in HDP, prior to diagnosis.
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INTRODUCTION: There is evidence for fetal sex-dependent differences in the way in which preeclamptic pregnancies proceed, and in maternal and neonatal outcomes. Mouse models are common in the study of preeclampsia and pooled tissue from multiple placentae is often used to obtain samples for expression studies. Potential concerns regarding this practice are the sex-dependent differences in placental expression of candidate factors. One biomolecule of interest is soluble fms-like tyrosine kinase 1 (sFLT-1) which is a known marker of preeclampsia and commonly used to determine the severity of the induced preeclampsia-like syndrome in rodent models. OBJECTIVES: It was the aim of this preliminary study to determine whether variation exists in the expression of different genes in murine placenta based on pup sex in C57BL/6JArc mice. A novel gene, Jumonji domain-containing protein 6 (Jmjd6) that may prove to have a role in the pathogenesis of preeclampsia, mFLT-1 and sFLT-1 were selected as targets. METHODS: Seventeen pups were retrieved from three normal pregnant female mice euthanized via cervical dislocation (CD) on day 17.5 or 18.5. Tails and corresponding placentas were collected from the pups, snap frozen in liquid nitrogen and stored at -80°C. Tails were used to accurately determine pup sex via PCR amplification of sex chromosome-specific sequences and revealed the presence of 3 females and 14 males. Quantitative PCR was used to determine the relative expression of the FLT-1 and Jmjd6 transcripts in each placenta. The placenta collected from the first pup of the first pregnant female served as the reference sample and transcript expression in the remaining samples was expressed relative to this sample. General linear modelling using linear regression with categorical variables was used to evaluate the difference in transcript expression between the sexes and Pearson's correlation coefficient used to examine relationships between variables. RESULTS: Pup sex was found to have a significant effect on the relative expression of sFLT-1 after controlling for litter, pup weight and gestational age (p=0.013), with 1.5 times more expression in the placentas of female pups. The expression of sFLT-1 was highly correlated with mFLT-1 (r=0.690,p=0.002). The relative expression of Jmjd6 was not significantly different in male and female placentas and sFlt-1 was not correlated with Jmjd6. CONCLUSION: This is the first study to demonstrate a link between fetal sex and placental sFLT-1 expression in mice, finding increased levels of this gene in the placentas of female pups. It is possible that in normal pregnancies, female placentas produce more sFLT-1 which acts to condition them and offer some protection during the sFLT-1 spike seen in preeclampsia. The findings of this study also highlight a possible need to consider sex as a variable in placental expression studies using mice to ensure the accuracy of results.
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INTRODUCTION: Biomolecules such as soluble fms-like tyrosine kinase 1 (sFLT-1) have been implicated in the pathogenesis of preeclampsia with many studies reporting on their expression in human placenta. OBJECTIVES: This study aimed to determine whether variation exists in the expression of different genes in human placenta based on collection site. Expression of different FLT-1 variants including the primate-specific sFLT-1e15a and a novel gene, Jumonji domain-containing protein 6 (Jmjd6) that may prove to have a role in the pathogenesis of preeclampsia, was selected as targets. METHODS: Placental tissue was collected from one normotensive and one preeclamptic woman following caesarean section at 38 weeks. Twelve 1.5cm diameter×2mm thick samples were excised from various sites around the decidual surface. Quantitative PCR was used to determine the relative expression of the FLT-1 and Jmjd6 transcripts in the separate samples. Within a placenta, the first sample collected served as the reference and transcript expression in the remaining 11 samples was expressed relative to this sample. Between placentas, a pooled normal sample was used as a reference to determine the relative expression in preeclamptic compared to normal placental samples. One sample t -tests and coefficients of variation (CV) were used to explore the variation and Pearson's correlation coefficient was used to examine relationships. RESULTS: Within the normal placenta, significant variation was seen in the 12 collection sites for sFLT-1 e15a (CV=45.1% p=0.008) and Jmjd6 (CV=30.4% p=0.019). The CVs for sFLT-1 i13 and mFLT-1 were 25.6% and 23.7% respectively. Within the preeclamptic placenta, significant variation was seen in the expression of all FLT-1 variants; mFLT-1 (CV=66.9% p=0.023), sFLT-1 i13 (CV=64.8% p=0.033) and sFLT-1 e15a (CV=61.1% p=0.001) across different collection sites. Significant variation was also seen between preeclamptic placenta sites and a normotensive pool; mFLT-1 (CV=66.9% p=0.012), sFLT-1 e15a (CV=61.1% p=0.005) and Jmjd6(CV=65.2% p=0.029). Using cumulative moving means, the minimum number of samples required to obtain a zero difference in means for all transcripts in a data subset was 8 for the normal placenta and 6 for the preeclamptic placenta. Overall, the expression of Jmjd6 and all FLT-1 variants was increased in the samples from the preeclamptic placenta compared to normal. Expression of mFLT-1 was highly correlated with sFLT-1 i13 and sFLT-1 e15ain preeclamptic (r=0.808 p=0.001; r=0.841p=0.001) but not normal placenta, and Jmjd6 was not correlated with any transcript in either placenta. CONCLUSION: This study demonstrates significant variation in expression levels of several new and commonly investigated genes across sites in both normal and preeclamptic human placenta. These data show samples should be obtained from no less than 8 separate sites when pooling samples for expression analysis. Further, given that many studies examine relationships between different colocalised molecules, it may also be prudent to examine expression levels in each site separately to ensure that no relationships are missed.
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INTRODUCTION: Hypertensive disorders of pregnancy (HDP) remain a leading cause of maternal and perinatal morbidity and mortality worldwide. In Australia approximately 10% of all pregnancies are affected by HDP. There is growing evidence that endothelial damage caused by HDP remains after pregnancy and has long term consequences on maternal health. OBJECTIVES: The aim of our research was to determine the association between HDP and risk of having high blood pressure in later life. METHODS: Self-reported data regarding a physician's diagnosis of HDP and of high blood pressure later in life were obtained from women recruited from the 45 and Up Study, Australia. Relative risks (converted from odds ratios) and 99% confidence intervals were estimated using logistic regression, adjusting for demographic and lifestyle characteristics. RESULTS: A total of 82,164 women were included in the study, of which 9,845 reported having HDP. Women who had HDP had a significantly increased risk of having high blood pressure later in life compared to women who did not have HDP (adjusted relative risk of 2.05, 99% CI 1.99-2.11, p<0.001). The results showed that women who had HDP develop high blood pressure 6.3 years (99% CI 5.85-6.66, p<0.001) earlier compared to women without HDP. CONCLUSION: Women who have HDP are at a greater risk of future onset of high blood pressure compared to women who have a healthy pregnancy. Women with HDP should be monitored closely in the years following pregnancy for early identification and intervention of high blood pressure.
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INTRODUCTION: Experimental manipulation of the maternal environment in animal models has assisted with our understanding of the mechanisms contributing to fetal programming. Evidence suggests that individuals who experience a suboptimal intrauterine milieu have an increased risk of developing disease later in life. Preeclampsia is a complication of pregnancy known to alter the fetal environment. Such alterations lead to programming of the fetus for subsequent susceptibility to cardiovascular disease, including hypertension. Studies indicate that offspring from women with hypertensive disorders of pregnancy are at an increased risk of cardiovascular complications later in life. OBJECTIVES: To investigate whether offspring of experimental preeclamptic baboon pregnancies have higher blood pressure compared with offspring of their experimental controls and those of normotensive pregnancies. This is a pilot study to assess the feasibility of measuring health outcomes and risk factors for experimental preeclampsia offspring. METHODS: We have successfully developed two models of preeclampsia in the baboon (Papio hamadryas) through induction of uteroplacental ischemia in late pregnancy and TNFα infusion mid pregnancy. Systolic and diastolic blood pressure (SBP, DBP) were measured in baboon offspring from experimental preeclamptic (EPE, n=4), experimental preeclamptic control (EPE control, n=4) and normotensive pregnancies (Normal, n=12) using indirect sphygmomanometry (first and fourth Korotkoff sounds recorded). Each measurement was taken three times under identical anaesthetic and environmental conditions. Data are reported as the average ± standard deviation. A generalized linear model was applied to the data and adjusted for age and sex. RESULTS: There was no significant difference in SBP of offspring from EPE (97.3±7.2mm Hg, P=0.21) or EPE control (108.4±7.3mm Hg, P=0.16) when compared with offspring of normotensive pregnancies (102.6±7.3mm Hg). Similarly, there was no difference in DBP of offspring from EPE (67.5±15.4 mm Hg, P=0.72) or EPE control (61.5±15.7mm Hg, P=0.79) compared with normotensive offspring (63.9±16.7mm Hg). There was a significant difference in SBP and DBP of young (<5yrs) compared to older (⩾5yrs) animals (SBP: 96.4±7.9 versus 109.1±7.5mm Hg, P=0.003; DBP: 54.3±17.2 versus 74.4±16.4mm Hg, P=0.009). There were no differences in SBP or DBP between male and female offspring (102.1±7.7 versus 103.4±8.3mm Hg, P=0.70; 63.9±16.8 versus 64.8±18.4mm Hg, P=0.90 respectively). CONCLUSION: This study has shown that offspring from experimental preeclamptic pregnancies survive and are able to undergo long-term testing of blood pressure. There does not appear to be any significant differences in blood pressure among EPE offspring and their controls. However, the opportunity to investigate offspring over an extended period of time is feasible. This will enable us to examine other parameters that affect BP of experimental preeclampsia offspring.
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OBJECTIVE: To investigate whether the lifetime number of affective episodes or illness duration is associated with changes in local grey matter volume, in patients with bipolar I disorder without comorbid conditions. METHOD: Magnetic resonance imaging scans of 55 patients with bipolar I disorder were analysed using VBM. RESULTS: Smaller grey matter volume in the inferior frontal gyri of the dorsolateral prefrontal cortices (DLPFC) correlated significantly to the lifetime number of manic episodes. No association between local grey matter volume and the lifetime number of depression episodes or illness duration was found. CONCLUSION: We found strong evidence for a linear correlation between a decrease in DLPFC volume and the lifetime number of manic episodes in patients with bipolar I disorder. Interestingly, DLPFC is known to be important for executive functions and the findings in this study might hence be linked to the executive cognitive deficits associated with bipolar disorder.
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Trastorno Bipolar/patología , Mapeo Encefálico/métodos , Encéfalo/patología , Imagen por Resonancia Magnética/métodos , Vaina de Mielina/patología , Adulto , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional/métodos , Masculino , Corteza Prefrontal/patología , Factores de TiempoRESUMEN
BACKGROUND/AIMS: Autosomal dominant hypocalcaemia (ADH) is caused by activating mutations in the calcium- sensing receptor (CASR). We aimed to describe the phenotypic variation within a large family with ADH, especially kidney and cerebral basal ganglia calcifications. METHODS: Fifteen related subjects carrying the CASR mutation T151M participated in a cross-sectional study of calcium homeostasis, renal ultrasonography, cerebral CT, bone mineral density, and health-related quality of life (HRQoL). RESULTS: Eight subjects had received vitamin D treatment (mean duration 15.3 years; range 11-20 years). Urinary calcium excretion was elevated in 5/8 vitamin-D-treated and in 3/7 untreated subjects. Serum magnesium, calcium and parathyroid hormone remained at the lower reference limit or below. Renal calcifications were found in 12 of 14 (86%) and basal ganglia calcifications in 5 of 11 (46%) subjects, independently of vitamin D therapy. The glomerular filtration rate was moderately reduced in 3 subjects. Mean bone mineral density and bone markers were normal. HRQoL was impaired in the vitamin-D-treated group despite correction of the hypocalcaemia. CONCLUSIONS: The impact of the CASR mutation on calcium homeostasis varied greatly. Kidney and basal ganglia calcifications are common in ADH independently of vitamin D treatment, which, however, increases urinary calcium excretion and may promote urolithiasis.
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Hipocalcemia/genética , Receptores Sensibles al Calcio/metabolismo , Adolescente , Adulto , Anciano , Densidad Ósea/genética , Calcinosis/genética , Calcio/metabolismo , Calcio/orina , Cerebro/metabolismo , Cerebro/patología , Estudios Transversales , Femenino , Humanos , Hipocalcemia/metabolismo , Hipocalcemia/patología , Hipocalcemia/orina , Riñón/diagnóstico por imagen , Riñón/metabolismo , Riñón/patología , Masculino , Persona de Mediana Edad , Mutación , Hormona Paratiroidea/sangre , Linaje , Fenotipo , Receptores Sensibles al Calcio/genética , Análisis de Secuencia de ADN , Estadísticas no Paramétricas , Ultrasonografía , Adulto JovenRESUMEN
A fast, sensitive, universal and accurate method for the determination of four different tyrosine kinase inhibitors from biological material was developed using LC-MS/MS techniques. Utilizing a simple protein precipitation with acetonitrile a 20 microl sample volume of biological matrixes can be extracted at 4 degrees C with minimal effort. After centrifugation the sample extract is introduced directly onto the LC-MS/MS system without further clean-up and assayed across a linear range of 1-4000 ng/ml. Chromatography was performed using a Dionex Ultimate 3000 with a Phenomenex prodigy ODS3 (2.0 mm x 100 mm, 3 microm) column and eluted at 200 microl/min with a tertiary mobile phase consisting of 20mM ammonium acetate:acetonitrile:methanol (2.5:6.7:8.3%). Injection volume varied from 0.1 microl to 1 microl depending on the concentration of the drug observed. Samples were observed to be stable for a maximum of 48 h after extraction when kept at 4 degrees C. Detection was performed using a turbo-spray ionization source and mass spectrometric positive multi-reaction-monitoring-mode (+MRM) for Gefitinib (447.1 m/z; 127.9 m/z), Erlotinib (393.9 m/z; 278.2 m/z), Sunitinib (399.1 m/z; 283.1 m/z) and Sorafenib (465.0 m/z; 251.9 m/z) at an ion voltage of +3500 V. The accuracy, precision and limit-of-quantification (LOQ) from cell culture medium were as follows: Gefitinib: 100.2+/-3.8%, 11.2 nM; Erlotinib: 101.6+/-3.7%, 12.7 nM; Sunitinib: 100.8+/-4.3%, 12.6 nM; Sorafenib: 93.9+/-3.0%, 10.8 nM, respectively. This was reproducible for plasma, whole blood, and serum. The method was observed to be linear between the LOQ and 4000 ng/ml for each analyte. Effectiveness of the method is illustrated with the analysis of samples from a cellular accumulation investigation and from determination of steady state concentrations in clinically treated patients.