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1.
J Evol Biol ; 27(3): 457-65, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24517341

RESUMO

Some of the genetic benefit hypotheses put forward to explain multiple male mating (polyandry) predict that sons of polyandrous females will have an increased competitive ability under precopulatory or post-copulatory competition via paternally inherited traits, such as attractiveness or fertilization efficiency. Here, we tested these predictions by comparing the competitive ability of sons of experimentally monandrous and polyandrous female bank voles (Myodes glareolus), while controlling for potential material and maternal effects. In female choice experiments, we found no clear preference for sons of either monandrous or polyandrous mothers. Moreover, neither male type was dominant over the other, indicating no advantage in precopulatory male contest competition. However, in competitive matings, sons of polyandrous mothers significantly increased their mating efforts (mating duration, intromission number). In line with this, paternity success was biased towards sons of polyandrous mothers. Because there was no evidence for maternal effects, our results suggest that female bank voles gain genetic benefits from polyandry.


Assuntos
Arvicolinae/fisiologia , Copulação , Comportamento Sexual Animal , Animais , Feminino , Masculino
3.
Osteoarthritis Cartilage ; 17(11): 1503-12, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19470416

RESUMO

OBJECTIVE: To investigate the effects of growth and differentiation factor-5 (GDF-5) alone or in combination with insulin on engineered cartilage from primary or expanded chondrocytes during 3-dimensional in vitro culture. DESIGN: Juvenile bovine chondrocytes were seeded either as primary or as expanded (passage 2) cells onto polyglycolic acid fiber meshes and cultured for 3 weeks in vitro. Additionally, adult human chondrocytes were grown in pellet culture after expansion (passage 2). The culture medium was supplemented either with GDF-5 in varying concentrations or insulin alone, or with combinations thereof. RESULTS: For primary chondrocytes, the combination of GDF-5 and insulin led to increased proliferation and construct weight, as compared to either factor alone, however, the production of glycosaminoglycans (GAG) and collagen per cell were not affected. With expanded bovine chondrocytes, the use of GDF-5 or insulin alone led to only very small constructs with no type II collagen detectable. However, the combination of GDF-5 (0.01 or 0.1 microg/ml) and insulin (2.5 microg/ml) yielded cartilaginous constructs and, in contrast to the primary cells, the observed redifferentiating effects were elicited on the cellular level independent of proliferation (increased production of GAG and collagen per cell, clear shift in collagen subtype expression with type II collagen observed throughout the construct). The synergistic redifferentiating effects of the GDF-5/insulin combination were confirmed with expanded adult human cells, also exhibiting a clear shift in collagen subtype expression on the mRNA and protein level. CONCLUSIONS: In combination with insulin, GDF-5 appears to enable the redifferentiation of expanded chondrocytes and the concurrent generation of cartilaginous constructs. The demonstration of these synergistic effects also for adult human chondrocytes supports the clinical relevance of the findings.


Assuntos
Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Colágeno Tipo II/metabolismo , Glicosaminoglicanos/metabolismo , Fator 5 de Diferenciação de Crescimento/biossíntese , Animais , Bovinos , Células Cultivadas , Colágeno Tipo II/genética , Fator 5 de Diferenciação de Crescimento/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Engenharia Tecidual
13.
Cochrane Database Syst Rev ; (4): CD004175, 2006 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-17054199

RESUMO

BACKGROUND: Kawasaki disease is the most common cause of acquired heart disease in children in developed countries. The coronary arteries supplying the heart can be damaged in Kawasaki disease. The principal advantage of timely diagnosis is the potential to prevent this complication with early treatment. Salicylate (acetyl salicylate acid (ASA), aspirin) and intravenous immunoglobulin (IVIG) are widely used for this purpose. Salicylate is largely otherwise avoided in children because of concerns about serious side effects, particularly the risk of Reyes syndrome. OBJECTIVES: The objective of this review was to evaluate the effectiveness of salicylate in treating and preventing cardiac consequences of Kawasaki disease in children. SEARCH STRATEGY: The Cochrane Peripheral Vascular Disease Group searched their trials register (last searched July 2006) and the Cochrane Central Register of Controlled Trials (CENTRAL) (last searched Issue 3, 2006). We searched MEDLINE (January 1966 to July 2006), EMBASE (January 1980 to July 2006), and CINAHL (1982 to July 2006), and reference list of articles. In addition we contacted experts in the field. SELECTION CRITERIA: Randomised controlled trials (RCTs) of salicylate to treat Kawasaki disease in children were eligible for inclusion. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial quality and extracted data. Study authors were contacted for additional information. MAIN RESULTS: We found one trial involving 102 children which was described as randomised, but it was not possible to confirm the method of treatment allocation. A second comparative study, possibly with a randomised treatment allocation, was also identified. The one randomised trial reported no association between the addition of ASA to IVIG treatment on the rate of coronary artery abnormalities at follow up, but with wide confidence limits. The second, possibly randomised trial did demonstrate a reduction in duration of fever with high dose ASA compared to low dose ASA, but was insufficiently powered to establish the effect on coronary artery abnormalities at follow up. AUTHORS' CONCLUSIONS: Until good quality RCTs are carried out, there is insufficient evidence to indicate whether children with Kawasaki disease should continue to receive salicylate as part of their treatment regimen.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Salicilatos/uso terapêutico , Criança , Humanos , Imunoglobulinas Intravenosas/uso terapêutico
15.
Arch Dis Child ; 90(11): 1122-7, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16131502

RESUMO

OBJECTIVE: To investigate to what extent prenatal, early postnatal, and late postnatal growth predicts risk of childhood obesity. METHODS: This was a historical cohort study of 1335 full term singletons born in southwest England in 1989. The main outcome measure was body mass index (BMI) at age 7. Absolute weights at birth, 6 weeks, and 18 months, and change in weights during the intervening periods were measured. Measures were examined as z scores standardised to the 1990 UK reference population. RESULTS: BMI at age 7 was positively associated with z scores for weight at all ages. Regression coefficients (95% confidence intervals) were: 0.16 (0.11 to 0.22), 0.19 (0.15 to 0.24), and 0.29 (0.26 to 0.33) for weights at birth, 6 weeks, and 18 months, respectively. Regression coefficients for birth weight, early weight gain (change in weight z score between birth and 6 weeks), and late weight gain (change in weight z score between 6 weeks and 18 months), adjusted for each other were: 0.32 (0.27 to 0.38), 0.31 (0.26 to 0.37), and 0.28 (0.23 to 0.32), respectively. There was no statistical evidence for interaction among weights, weight gains, or social deprivation. Social deprivation independently predicted BMI at age 7, the major influence being weight gain after 6 weeks of life. CONCLUSIONS: These data suggest that obesity risk is acquired gradually over the perinatal and postnatal periods, instead of during a prenatal or early postnatal critical window. The association of obesity risk with social circumstances and the timing of its origin offer pointers to some underlying determinants of obesity.


Assuntos
Desenvolvimento Fetal , Crescimento , Obesidade/etiologia , Antropometria , Peso ao Nascer , Índice de Massa Corporal , Métodos Epidemiológicos , Feminino , Humanos , Recém-Nascido , Masculino , Obesidade/embriologia , Aumento de Peso
19.
Arch Dis Child ; 89(3): 278-80, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14977713

RESUMO

This evidence based guideline covers the immediate management of a child presenting to hospital with a febrile or afebrile seizure, once the fit has stopped.


Assuntos
Convulsões/etiologia , Doença Aguda , Criança , Pré-Escolar , Diagnóstico Diferencial , Medicina Baseada em Evidências , Hospitalização , Humanos , Lactente , Convulsões/terapia , Convulsões Febris/etiologia , Convulsões Febris/terapia
20.
Arch Dis Child ; 88(12): 1126-7, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14670787

RESUMO

A well produced evidence based guideline has been developed in response to a national audit that demonstrated wide variations in the performance of sweat tests. Accurate and reliable sweat test results will be particularly important with the advent of neonatal screening. The guideline recommendations include the collection and analysis of sweat samples, and interpretation of results. It emphasises the importance of sweat chloride as the best discriminator.


Assuntos
Fibrose Cística/diagnóstico , Triagem Neonatal/normas , Guias de Prática Clínica como Assunto , Suor/química , Cloretos/análise , Medicina Baseada em Evidências , Humanos , Recém-Nascido , Triagem Neonatal/métodos , Sensibilidade e Especificidade , Manejo de Espécimes
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