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1.
Phys Rev Lett ; 115(4): 041101, 2015 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-26252674

RESUMO

The paucity of observed supermassive black hole binaries (SMBHBs) may imply that the gravitational wave background (GWB) from this population is anisotropic, rendering existing analyses suboptimal. We present the first constraints on the angular distribution of a nanohertz stochastic GWB from circular, inspiral-driven SMBHBs using the 2015 European Pulsar Timing Array data. Our analysis of the GWB in the ~2-90 nHz band shows consistency with isotropy, with the strain amplitude in l>0 spherical harmonic multipoles ≲40% of the monopole value. We expect that these more general techniques will become standard tools to probe the angular distribution of source populations.

2.
Early Hum Dev ; 91(5): 327-31, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25846842

RESUMO

BACKGROUND: The relative lengths of the index finger to the ring finger (2D:4D) is sexually dimorphic and is thought to be a correlate of prenatal sex steroids (low 2D:4D=high prenatal testosterone and low prenatal oestrogen). In adults there have been reports that low 2D:4D is consistently associated with high sports performance. AIMS: To investigate correlations between 2D:4D and fitness levels in children. STUDY DESIGN: Right 2D:4D and body size were measured, in addition to flexibility, speed, endurance and strength (Eurofit tests). SUBJECTS: 922 boys and 835 girls (mean ages (years): 10.8 ± 1.01 and 10.07 ± 1.00 respectively). OUTCOME MEASURES: height, mass, BMI, triceps and subscapular skinfolds, 20 m shuttle run, sit and reach, standing broad jump, hand grip strength, 10 × 5m sprint, and the sit and reach test. RESULTS: Boys significantly outperformed the girls in the 10 × 5m sprints, the 20 m shuttle run, standing broad jump, and hand grip strength. In boys but not girls, 2D:4D was significantly negatively correlated with scores in all these tests except the standing broad jump. In girls but not boys, 2D:4D was significantly positively correlated to stature, mass, BMI and waist circumference. CONCLUSIONS: It is suggested that high prenatal testosterone and low prenatal oestrogen (low 2D:4D) is implicated in high sprinting speed, endurance and hand grip strength in boys. In girls low prenatal testosterone and high prenatal oestrogen is associated with large body size.


Assuntos
Dedos/anatomia & histologia , Aptidão Física , Criança , Desenvolvimento Infantil , Estrogênios/metabolismo , Feminino , Humanos , Masculino , Caracteres Sexuais , Testosterona/metabolismo
3.
Eye (Lond) ; 29(4): 569-73, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25657041

RESUMO

PURPOSE: To investigate whether intravitreal ranibizumab injections administered to a child alter systemic plasma levels of total and free VEGF 165. METHODS: A 9-year-old child sustained a choroidal rupture from blunt trauma. He subsequently developed a secondary choroidal neovascular membrane, which was treated with five ranibizumab injections over a period of 8 months. Peripheral venous blood samples were taken at each visit over a period of 12 months and plasma was extracted. Plasma VEGF 165 levels were determined using enzyme-linked immunosorbent assay and were assayed both pre- and post-immunodepletion to remove complexed VEGF. RESULTS: Plasma VEGF 165 levels proved labile following intravitreal injection of ranibizumab. Levels increased by 30% above baseline following the first intravitreal ranibizumab injection, but then returned to baseline despite two subsequent injections. There was then a rebound increase of 67% in total plasma VEGF levels following a further injection, which remained above baseline for 12 weeks despite two further intravitreal ranibizumab injections. Baseline levels were re-attained 26 weeks after the final injection. CONCLUSIONS: These results suggest intravitreal ranibizumab injections can cause significant, multiphasic changes in systemic VEGF levels. This may be of particular clinical significance in children as VEGF is known to be vital in the development of major organs, in addition to its role in the maintenance of normal organ function in adults.


Assuntos
Inibidores da Angiogênese/farmacologia , Corioide/lesões , Neovascularização de Coroide/sangue , Neovascularização de Coroide/tratamento farmacológico , Ranibizumab/farmacologia , Fator A de Crescimento do Endotélio Vascular/sangue , Inibidores da Angiogênese/administração & dosagem , Criança , Humanos , Injeções Intravítreas , Masculino , Ranibizumab/administração & dosagem
4.
Ann Rheum Dis ; 74(6): 1138-44, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25269831

RESUMO

OBJECTIVE: To determine whether the addition of 26 weeks of subcutaneous peginterferon-α-2b could reduce the requirement for systemic corticosteroids and conventional immunosuppressive medication in patients with Behçet's disease (BD). METHODS: We conducted a multicentre randomised trial in patients with BD requiring systemic therapy. Patients were randomised to 26 weeks of peginterferon-α-2b in addition to their standard care or to standard care only and followed 6-monthly for 3 years with BD activity scores and quality of life questionnaires. Patients at one centre had blood taken to measure regulatory T cells (Tregs) and Th17 cells. RESULTS: 72 patients were included. At months 10-12, while among the entire patient population there was no difference in the corticosteroid dose or immunosuppression use between the treatment groups (adjusted OR 1.04, 95% CI 0.34 to 3.19), post hoc analysis revealed that in patients who were on corticosteroids at baseline the corticosteroid requirement was significantly lower in the peginterferon-α-2b (6.5 (5-15) mg/day) compared with the non-interferon group (10 (8.25-16.5) mg/day, p=0.039). Furthermore, there was a trend towards an improved quality of life that became significant by 36 months (p=0.008). This was associated with a significant rise in Tregs and a decrease in Th17 cells which was still present at 1 year and 6 months after the interferon was stopped. The safety profile was similar with adverse events in 10% in both groups. CONCLUSIONS: The addition of peginterferon-α-2b to the drug regime of BD patients did not significantly reduce their corticosteroid dose required at 1 year. However, in those on corticosteroids at baseline post hoc analysis demonstrated that the addition of peginterferon-α-2b did result in a significant reduction in corticosteroid dose with a significantly improved quality of life and trend to reduce other required immunosuppressive agents. This effect was seen at 1 year and associated with a rise in Tregs suggesting a possible mode for interferon action. TRIAL REGISTRATION NUMBER: ISRCTN 36354474; EudraCT 2004-004301-18.


Assuntos
Corticosteroides/administração & dosagem , Antivirais/uso terapêutico , Síndrome de Behçet/tratamento farmacológico , Imunossupressores/administração & dosagem , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Linfócitos T Reguladores/citologia , Células Th17/citologia , Adulto , Azatioprina/uso terapêutico , Síndrome de Behçet/imunologia , Ciclosporina/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Interferon alfa-2 , Contagem de Linfócitos , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Qualidade de Vida , Proteínas Recombinantes/uso terapêutico , Método Simples-Cego , Inquéritos e Questionários , Tacrolimo/uso terapêutico , Resultado do Tratamento
5.
Semin Cell Dev Biol ; 28: 22-30, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24680771

RESUMO

HB-EGF is a member of the EGF family of ligands that is initially synthesized as a membrane-bound growth factor termed, proHB-EGF. The membrane bound proHB-EGF undergoes extensive proteolytic processing by several metalloproteinases capable of stimulating cellular proliferation. Soluble, mature HB-EGF binds to and activates EGF receptors. HB-EGF is a critical molecular component to a number of normal physiological processes including but not limited to tissue injury and wound healing, reproduction, angiogenesis and recently, adipogenesis. Misexpression of HB-EGF is linked to tumor formation and cancer including hepatocellular, pancreatic, gastric, breast, colon and melanoma, gliomas and glioblastomas. HB-EGF is a likely tool for therapeutic approaches to enhance treatment of injuries as well as a target for prevention of several cancers and obesity.


Assuntos
Desintegrinas/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Fator de Crescimento Semelhante a EGF de Ligação à Heparina/metabolismo , Metaloproteases/metabolismo , Animais , Humanos , Morfogênese/fisiologia , Cicatrização/fisiologia
6.
Transl Psychiatry ; 3: e328, 2013 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-24301646

RESUMO

Recent genetic studies have linked mental illness to alterations in disrupted in schizophrenia 1 (DISC1), a multifunctional scaffolding protein that regulates cyclic adenosine monophosphate (cAMP) signaling via interactions with phosphodiesterase 4 (PDE4). High levels of cAMP during stress exposure impair function of the prefrontal cortex (PFC), a region gravely afflicted in mental illness. As stress can aggravate mental illness, genetic insults to DISC1 may worsen symptoms by increasing cAMP levels. The current study examined whether viral knockdown (KD) of the Disc1 gene in rat PFC increases susceptibility to stress-induced PFC dysfunction. Rats were trained in a spatial working memory task before receiving infusions of (a) an active viral construct that knocked down Disc1 in PFC (DISC1 KD group), (b) a 'scrambled' construct that had no effect on Disc1 (Scrambled group), or (c) an active construct that reduced DISC1 expression dorsal to PFC (Anatomical Control group). Data were compared with an unoperated Control group. Cognitive performance was assessed following mild restraint stress that had no effect on normal animals. DISC1 KD rats were impaired by 1 h restraint stress, whereas Scrambled, Control, and Anatomical Control groups were unaffected. Thus, knocking down Disc1 in PFC reduced the threshold for stress-induced cognitive dysfunction, possibly through disinhibited cAMP signaling at neuronal network synapses. These findings may explain why patients with DISC1 mutations may be especially vulnerable to the effects of stress.


Assuntos
Transtornos Cognitivos/metabolismo , Memória de Curto Prazo/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Córtex Pré-Frontal/fisiopatologia , Esquizofrenia/metabolismo , Estresse Psicológico/metabolismo , Animais , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/genética , AMP Cíclico/metabolismo , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Masculino , Proteínas do Tecido Nervoso/genética , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Sprague-Dawley , Restrição Física , Esquizofrenia/complicações , Esquizofrenia/genética , Transdução de Sinais , Estresse Psicológico/genética , Sinapses/metabolismo
7.
Growth Factors ; 31(6): 185-98, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24116709

RESUMO

Abnormal adipogenesis leads to excessive fat accumulation and several health disorders. Mouse fibroblasts (MLC) transfected with ADAM 12S and HB-EGF promoted lipid accumulation. Addition of KBR-7785, an ADAM 12S inhibitor, to HB-EGF/ADAM 12S expressing cells suppressed adipogenesis. BrdU incorporation was attenuated and enhanced mitotracker staining was observed in HB-EGF/ADAM 12S cells. Quantitative real time RT-PCR resulted in elevated levels of expression of three brown adipose tissue (BAT) genes (PRDM16, PGC-1α, and UCP-1), while expression levels of the three white adipose tissue (WAT) genes (PPARγ, C/EBPα, and AKT-1) were unaltered in HB-EGF/ADAM 12S cells. Amino- or carboxy-terminal deletions of HB-EGF (HB-EGFΔN and HB-EGFΔC) co-expressed with ADAM 12S stimulated lipid accumulation. Human epidermoid carcinoma cells (A431) also exhibited lipid accumulation by HB-EGF/ADAM 12S co-expression. These studies suggest ADAM 12S and HB-EGF are involved in cellular plasticity resulting in the production of BAT-like cells and offers insight into novel therapeutic approaches for fighting obesity.


Assuntos
Proteínas ADAM/genética , Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/metabolismo , Diferenciação Celular , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Membrana/genética , Proteína ADAM12 , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Animais , Carcinoma de Células Escamosas , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Fibroblastos , Expressão Gênica , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Metabolismo dos Lipídeos , Inibidores de Metaloproteinases de Matriz/farmacologia , Camundongos , Fenótipo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Transfecção
8.
Early Hum Dev ; 89(8): 589-92, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23578732

RESUMO

BACKGROUND: There is limited literature on the relationship between second to fourth finger digit ratio (2D:4D) and health- and skill-related fitness in children. To examine this relationship it is important to establish a reliable method of assessing 2D:4D for use with large groups of children. AIM: The aim of the study was to examine the reliability of a field-based 2D:4D measure in children. METHODS/RESEARCH DESIGN: Fifty 8-11 year olds had 2D:4D of the right hand measured using a Perspex table top, a digital camera, and Adobe Photoshop software. Second to fourth finger digit ratio (and 2D and 4D) intra-observer and inter-observer reliabilities were assessed on the same day and intraobserver reliability was measured between days. Limits of agreement (LoA), coefficient of variation (CV) and Pearson's correlation coefficient were used for statistical analysis. RESULTS: High correlation coefficients (r=0.95-0.99) and low CV's (0.4-1.2%) were reported for intra- and inter-observer reliabilities on the same day and between days. LoA revealed negligible systematic bias with random error ranging from 0.02 to 0.12. CONCLUSION: These findings suggest that 2D:4D (and 2D and 4D) assessment in children using digital photography provides a reliable measure of 2D:4D that can be used during field-based testing.


Assuntos
Precisão da Medição Dimensional , Dedos/anatomia & histologia , Criança , Feminino , Dedos/crescimento & desenvolvimento , Humanos , Masculino , Variações Dependentes do Observador , Fotografação
9.
IET Syst Biol ; 5(1): 50, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21261402

RESUMO

Classical sensitivity analysis is routinely used to identify points of fragility or robustness in biochemical networks. However, intracellular systems often contain components that number in the thousands to tens or less and consequently motivate a stochastic treatment. Although methodologies exist to quantify sensitivities in stochastic models, they differ substantially from those used in deterministic regimes. Therefore it is not possible to tell whether observed differences in sensitivity measured in deterministic and stochastic elaborations of the same network are the result of methodology or model form. The authors introduce here a distribution-based methodology to measure sensitivity that is equally applicable in both regimes, and demonstrate its use and applicability on a sophisticated mathematical model of the mouse circadian clock that is available in both deterministic and stochastic variants. The authors use the method to produce sensitivity measurements on both variants. They note that the rank-order sensitivity of the clock to parametric perturbations is extremely well conserved across several orders of magnitude. The data show that the clock is fragile to perturbations in parameters common to the cellular machinery ('global' parameters) and robust to perturbations in parameters that are clock-specific ('local' parameters). The sensitivity measure can be used to reduce the model from its original 73 ordinary differential equations (ODEs) to 18 ODEs and to predict the degree to which parametric perturbation can distort the phase response curve of the clock. Finally, the method is employed to evaluate the effect of transcriptional and translational noise on clock function. [Includes supplementary material].


Assuntos
Modelos Biológicos , Processos Estocásticos , Animais , Modelos Teóricos
10.
Eur J Ophthalmol ; 17(3): 336-40, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17534813

RESUMO

PURPOSE: To study phacoemulsification in vitrectomized eyes under topical anesthesia, assessing anesthetic and intraoperative characteristics and complications. METHODS: A prospective study was performed on 52 eyes of 51 patients who underwent phacoemulsification of cataract with intraocular lens implantation under topical anesthesia, having previously undergone pars plana vitrectomy. Surgical and anesthetic observations and complications were recorded, as were visual outcomes. RESULTS: Ninety-two percent of patients had improved visual acuity postoperatively with only one patient having visual loss as a result of surgery. The most common intraoperative observations were of a deep anterior chamber, posterior capsular plaques, posterior synechiae, and nuclear sclerotic cataracts. Topical anesthesia proved satisfactory in 96%, with only two patients requiring intracameral lignocaine 1%; no patients required conversion to injection anesthesia. There were no major operative or postoperative complications. CONCLUSIONS: Phacoemulsification in vitrectomized eyes can be challenging, but is visually rewarding. Topical anesthesia proved satisfactory for the vast majority of cases, with none of our patients requiring conversion to injection anesthesia.


Assuntos
Anestesia Local/métodos , Anestésicos Locais/administração & dosagem , Facoemulsificação/métodos , Propoxicaína/administração & dosagem , Vitrectomia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Complicações Intraoperatórias , Implante de Lente Intraocular , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Acuidade Visual
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