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1.
Nutrients ; 13(1)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466826

RESUMO

Iodine is essential for normal thyroid function, supporting healthy fetal and child development. Iodine requirements increase in pregnancy, but many women in regions without salt iodization have insufficient intakes. We explored associations between iodide intake and urinary iodine concentration (UIC), urinary iodine/creatinine ratio (I/Cr), thyroid stimulating hormone, thyroglobulin, free triiodothyronine, free thyroxine and palpable goiter in a region of mild-to-moderate iodine insufficiency. A total of 246 pregnant women aged 18-40 in Bradford, UK, joined the Health and Iodine in Babies (Hiba) study. They provided detailed information on diet and supplement use, urine and serum samples and were assessed for goiter at around 12, 26 and 36 weeks' gestation, and 6, 18 and 30 weeks postpartum. Dietary iodide intake from food and drink was estimated using six 24 h recalls. During pregnancy, median (IQR) dietary iodide intake was 101 µg/day (54, 142), with 42% from dairy and 9% from white fish. Including supplements, intake was 143 µg/day (94, 196), with 49% < UK reference nutrient intake (140 µg/day). Women with Pakistani heritage had 129 µg/day (87, 190) median total intake. Total intake during pregnancy was associated with 4% (95% CI: 1%, 7%) higher UIC, 5% (3%, 7%) higher I/Cr, 4% (2%, 6%) lower thyroglobulin and 21% (9%, 32%) lower odds of palpable goiter per 50 µg/day. This cohort consumed less iodide in pregnancy than UK and World Health Organization dietary recommendations. UIC, I/Cr and thyroglobulin were associated with intake. Higher intake was associated with fewer goiters. Because dairy was the dominant source of iodide, women following plant-based or low-dairy diets may be at particular risk of iodine insufficiency.


Assuntos
Deficiências Nutricionais , Iodetos/análise , Iodo , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Hormônios Tireóideos/sangue , Adolescente , Adulto , Deficiências Nutricionais/sangue , Deficiências Nutricionais/epidemiologia , Deficiências Nutricionais/urina , Dieta/estatística & dados numéricos , Suplementos Nutricionais/estatística & dados numéricos , Feminino , Humanos , Iodo/deficiência , Iodo/urina , Período Pós-Parto/fisiologia , Gravidez/estatística & dados numéricos , Reino Unido , Adulto Jovem
2.
Paediatr Perinat Epidemiol ; 35(2): 236-246, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32870514

RESUMO

BACKGROUND: Maternal iodine requirements increase during pregnancy to supply thyroid hormones critical for fetal neurodevelopment. Iodine insufficiency may result in poorer cognitive or child educational outcomes but current evidence is sparse and inconsistent. OBJECTIVES: To quantify the association between maternal iodine status and child educational outcomes. METHODS: Urinary iodine concentrations (UIC) and iodine/creatinine ratios (I:Cr) were measured in 6971 mothers at 26-28 weeks' gestation participating in the Born in Bradford cohort. Maternal iodine status was examined in relation to child school achievement (early years foundation stage (EYFS), phonics, and Key Stage 1 (KS1)), other learning outcomes, social and behavioural difficulties, and sensorimotor control in 5745 children aged 4-7 years. RESULTS: Median (interquartile range) UIC was 76 µg/L (46, 120), and I:Cr was 83 µg/g (59, 121). Overall, there was no strong or consistent evidence to support associations between UIC or I:Cr and neurodevelopmental outcomes. For instance, predicted EYFS and phonics scores (primary outcomes) at the 25th vs 75th I:Cr percentiles (99% confidence intervals) were similar, with no evidence of associations: EYFS scores were 32 (99% CI 31, 33) and 33 (99% CI 32, 34), and phonics scores were 34 (99% CI 33, 35) and 35 (99% CI 34, 36), respectively. CONCLUSIONS: In the largest single study of its kind, there was little evidence of detrimental neurodevelopmental outcomes in children born to pregnant women with iodine insufficiency as defined by World Health Organization-outlined thresholds. Alternative functional biomarkers for iodine status in pregnancy and focused assessment of other health outcomes may provide additional insight.


Assuntos
Iodo , Criança , Cognição , Feminino , Idade Gestacional , Humanos , Estado Nutricional , Gravidez , Gravidez Múltipla , Reino Unido/epidemiologia
3.
BMC Pediatr ; 20(1): 544, 2020 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-33276760

RESUMO

BACKGROUND: Maternal iodine requirements increase during pregnancy to supply thyroid hormones essential for fetal brain development. Maternal iodine deficiency can lead to hypothyroxinemia, a reduced fetal supply of thyroid hormones which, in the first trimester, has been linked to an increased risk of autism spectrum disorder (ASD) in the child. No study to date has explored the direct link between maternal iodine deficiency and diagnosis of ASD in offspring. METHODS: Urinary iodine concentrations (UIC) and iodine/creatinine ratios (I:Cr) were measured in 6955 mothers at 26-28 weeks gestation participating in the Born in Bradford (BiB) cohort. Maternal iodine status was examined in relation to the probability of a Read (CTV3) code for autism being present in a child's primary care records through a series of logistic regression models with restricted cubic splines. RESULTS: Median (inter-quartile range) UIC was 76 µg/L (46, 120) and I:Cr was 83 µg/g (59, 121) indicating a deficient population according to WHO guidelines. Ninety two children (1·3%) in our cohort had received a diagnosis of ASD by the census date. Overall, there was no evidence to support an association between I:Cr or UIC and ASD risk in children aged 8-12 years (p = 0·3). CONCLUSIONS: There was no evidence of an increased clinical ASD risk in children born to mothers with mild-to-moderate iodine deficiency at 26 weeks gestation. Alternative functional biomarkers of exposure and a wider range of conditions may provide further insight.


Assuntos
Transtorno do Espectro Autista , Iodo , Transtorno do Espectro Autista/etiologia , Criança , Feminino , Desenvolvimento Fetal , Idade Gestacional , Humanos , Gravidez , Reino Unido/epidemiologia
4.
BMC Med ; 18(1): 132, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32522280

RESUMO

BACKGROUND: Severe iodine insufficiency in pregnancy has significant consequences, but there is inadequate evidence to indicate what constitutes mild or moderate insufficiency, in terms of observed detrimental effects on pregnancy or birth outcomes. A limited number of studies have examined iodine status and birth outcomes, finding inconsistent evidence for specific outcomes. METHODS: Maternal iodine status was estimated from spot urine samples collected at 26-28 weeks' gestation from 6971 mothers in the Born in Bradford birth cohort. Associations with outcomes were examined for both urinary iodine concentration (UIC) and iodine-to-creatinine ratio (I:Cr). Outcomes assessed included customised birthweight (primary outcome), birthweight, small for gestational age (SGA), low birthweight, head circumference and APGAR score. RESULTS: There was a small positive association between I:Cr and birthweight in adjusted analyses. For a typical participant, the predicted birthweight centile at the 25th percentile of I:Cr (59 µg/g) was 2.7 percentage points lower than that at the 75th percentile of I:Cr (121 µg/g) (99% confidence interval (CI) 0.8 to 4.6), birthweight was predicted to be 41 g lower (99% CI 13 to 69) and the predicted probability of SGA was 1.9 percentage points higher (99% CI 0.0 to 3.7). There was no evidence of associations using UIC or other birth outcomes, including stillbirth, preterm birth, ultrasound growth measures or congenital anomalies. CONCLUSION: Lower maternal iodine status was associated with lower birthweight and greater probability of SGA. Whilst small, the effect size for lower iodine on birthweight is comparable to environmental tobacco smoke exposure. Iodine insufficiency is avoidable, and strategies to avoid deficiency in women of reproductive age should be considered. TRIAL REGISTRATION: ClinicalTrials.gov NCT03552341. Registered on June 11, 2018.


Assuntos
Anormalidades Congênitas/epidemiologia , Retardo do Crescimento Fetal/epidemiologia , Iodo/metabolismo , Mães/estatística & dados numéricos , Resultado da Gravidez/epidemiologia , Adulto , Peso ao Nascer , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Reino Unido
5.
Nutrients ; 11(2)2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30791590

RESUMO

Severe iodine deficiency in mothers is known to impair foetal development. Pregnant women in the UK may be iodine insufficient, but recent assessments of iodine status are limited. This study assessed maternal urinary iodine concentrations (UIC) and birth outcomes in three UK cities. Spot urines were collected from 541 women in London, Manchester and Leeds from 2004⁻2008 as part of the Screening for Pregnancy End points (SCOPE) study. UIC at 15 and 20 weeks' gestation was estimated using inductively coupled plasma-mass spectrometry (ICP-MS). Associations were estimated between iodine status (UIC and iodine-to-creatinine ratio) and birth weight, birth weight centile (primary outcome), small for gestational age (SGA) and spontaneous preterm birth. Median UIC was highest in Manchester (139 µg/L, 95% confidence intervals (CI): 126, 158) and London (130 µg/L, 95% CI: 114, 177) and lowest in Leeds (116 µg/L, 95% CI: 99, 135), but the proportion with UIC <50 µg/L was <20% in all three cities. No evidence of an association was observed between UIC and birth weight centile (-0.2% per 50 µg/L increase in UIC, 95% CI: -1.3, 0.8), nor with odds of spontaneous preterm birth (odds ratio = 1.00, 95% CI: 0.84, 1.20). Given the finding of iodine concentrations being insufficient according to World Health Organization (WHO) guidelines amongst pregnant women across all three cities, further studies may be needed to explore implications for maternal thyroid function and longer-term child health outcomes.


Assuntos
Iodo/deficiência , Estado Nutricional , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Fenômenos Fisiológicos da Nutrição Pré-Natal , Adulto , Peso ao Nascer , Cidades , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Iodo/urina , Avaliação Nutricional , Gravidez , Complicações na Gravidez/etiologia , Complicações na Gravidez/urina , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Diagnóstico Pré-Natal/métodos , Reino Unido/epidemiologia
6.
Sci Rep ; 6: 34848, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27713504

RESUMO

Metabolomics studies of low-biomass organisms, such as small insects, have previously relied on the pooling of biological samples to overcome detection limits, particularly using NMR. We show that the differentiation of metabolite profiles of individual 1 mg parasitoid wasps of different ages is possible when using a modified sample preparation and a combination of untargeted NMR and LC-MS based metabolomics. Changes were observed between newly emerged and older wasps in glycerolipids, amino acids and circulatory sugars. This advance in chemical profiling has important implications for the study of the behaviour and ecology of parasitoids and many other species of small organisms because predictions and observations are typically made at the level of the individual. Thus, the metabolomic state of low-biomass individuals can now be related to their behaviour and ecological performance. We discuss specifically the utility of age-related metabolomic profiling but our new approach can be applied to a wide range of biological research.


Assuntos
Envelhecimento/fisiologia , Metabolômica/métodos , Vespas/metabolismo , Animais , Cromatografia Líquida , Feminino , Metabolismo dos Lipídeos , Espectroscopia de Ressonância Magnética , Mariposas/parasitologia , Espectrometria de Massas por Ionização por Electrospray , Vespas/química , Vespas/fisiologia
7.
Sci Rep ; 5: 8043, 2015 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-25622726

RESUMO

Many animals avoid attack from predators through toxicity or the emission of repellent chemicals. Defensive mimicry has evolved in many species to deceive shared predators, for instance through colouration and other morphological adaptations, but mimicry hardly ever seems to involve multi-trait similarities. Here we report on a wingless parasitoid wasp that exhibits a full spectrum of traits mimicing ants and affording protection against ground-dwelling predators (wolf spiders). In body size, morphology and movement Gelis agilis (Ichneumonidae) is highly similar to the black garden ant (Lasius niger) that shares the same habitat. When threatened, G. agilis also emits a volatile chemical that is similar to an ant-produced chemical that repels spiders. In bioassays with L. niger, G. agilis, G. areator, Cotesia glomerata and Drosophila melanogaster, ants and G. agilis were virtually immune to spider attack, in contrast the other species were not. Volatile characterisation with gas chromatography-mass spectrometry identified G. agilis emissions as 6-methyl-5-hepten-2-one, a known insect defence semiochemical that acts as an alarm pheromone in ants. We argue that multi-trait mimicry, as observed in G. agilis, might be much more common among animals than currently realized.


Assuntos
Formigas/parasitologia , Comportamento Predatório/fisiologia , Vespas/fisiologia , Animais , Formigas/fisiologia , Tamanho Corporal , Drosophila melanogaster/fisiologia , Ecossistema , Cromatografia Gasosa-Espectrometria de Massas , Cetonas/análise , Aranhas/fisiologia , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Vespas/química
8.
Entomol Exp Appl ; 155(1): 1-17, 2015 04.
Artigo em Inglês | MEDLINE | ID: mdl-27478203

RESUMO

Metabolomic analyses can reveal associations between an organism's metabolome and further aspects of its phenotypic state, an attractive prospect for many life-sciences researchers. The metabolomic approach has been employed in some, but not many, insect study systems, starting in 1990 with the evaluation of the metabolic effects of parasitism on moth larvae. Metabolomics has now been applied to a variety of aspects of insect biology, including behaviour, infection, temperature stress responses, CO 2 sedation, and bacteria-insect symbiosis. From a technical and reporting standpoint, these studies have adopted a range of approaches utilising established experimental methodologies. Here, we review current literature and evaluate the metabolomic approaches typically utilised by entomologists. We suggest that improvements can be made in several areas, including sampling procedures, the reduction in sampling and equipment variation, the use of sample extracts, statistical analyses, confirmation, and metabolite identification. Overall, it is clear that metabolomics can identify correlations between phenotypic states and underlying cellular metabolism that previous, more targeted, approaches are incapable of measuring. The unique combination of untargeted global analyses with high-resolution quantitative analyses results in a tool with great potential for future entomological investigations.

9.
PLoS One ; 8(7): e68191, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23844170

RESUMO

The survival of a species depends on its capacity to adjust to changing environmental conditions, and new stressors. Such new, anthropogenic stressors include the neonicotinoid class of crop-protecting agents, which have been implicated in the population declines of pollinating insects, including honeybees (Apis mellifera). The low-dose effects of these compounds on larval development and physiological responses have remained largely unknown. Over a period of 15 days, we provided syrup tainted with low levels (2 µg/L(-1)) of the neonicotinoid insecticide imidacloprid to beehives located in the field. We measured transcript levels by RNA sequencing and established lipid profiles using liquid chromatography coupled with mass spectrometry from worker-bee larvae of imidacloprid-exposed (IE) and unexposed, control (C) hives. Within a catalogue of 300 differentially expressed transcripts in larvae from IE hives, we detect significant enrichment of genes functioning in lipid-carbohydrate-mitochondrial metabolic networks. Myc-involved transcriptional response to exposure of this neonicotinoid is indicated by overrepresentation of E-box elements in the promoter regions of genes with altered expression. RNA levels for a cluster of genes encoding detoxifying P450 enzymes are elevated, with coordinated downregulation of genes in glycolytic and sugar-metabolising pathways. Expression of the environmentally responsive Hsp90 gene is also reduced, suggesting diminished buffering and stability of the developmental program. The multifaceted, physiological response described here may be of importance to our general understanding of pollinator health. Muscles, for instance, work at high glycolytic rates and flight performance could be impacted should low levels of this evolutionarily novel stressor likewise induce downregulation of energy metabolising genes in adult pollinators.


Assuntos
Abelhas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Inseticidas/farmacologia , Redes e Vias Metabólicas/genética , Animais , Abelhas/metabolismo , Metabolismo dos Carboidratos/genética , Cromatografia Líquida , Sistema Enzimático do Citocromo P-450/genética , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Ontologia Genética , Glicólise/genética , Proteínas de Choque Térmico HSP90/genética , Imidazóis/farmacologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Larva/efeitos dos fármacos , Larva/genética , Larva/metabolismo , Metabolismo dos Lipídeos/genética , Lipídeos/análise , Espectrometria de Massas , MicroRNAs/genética , Neonicotinoides , Nitrocompostos/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNA/métodos
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