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1.
Ir J Med Sci ; 187(3): 701-708, 2018 Aug.
Article de Anglais | MEDLINE | ID: mdl-29353417

RÉSUMÉ

BACKGROUND: Dietary advice is a standard component of treatment for pregnant women with impaired glucose tolerance (IGT) and gestational diabetes (GDM), yet few studies report glycemic profiles in response to dietary therapies and the optimal dietary approach remains uncertain. AIM: To assess changes in maternal glycemic profile and pregnancy outcomes among women with diet-controlled IGT and GDM. METHODS: Pregnant women who had one or more elevated values on a 3-h oral glucose tolerance test were enrolled. All participants received dietary advice and glucose monitoring as part of routine clinical care. Fasting and 1-h post-prandial blood samples, collected prior to initiation of clinical treatment and repeated 4-6 weeks later, were analyzed for glucose, insulin, and C-peptide. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Women who required pharmacological therapy for glucose control were excluded from analyses. RESULTS: Participants (N = 93) were of moderately older age (mean 33 years), with a high rate of overweight/obesity (mean body mass index (BMI) = 28.65 kg/m2), and were diagnosed late in gestation (mean 29 weeks). Fasting (mean ± SD 4.82 ± 0.53 to 4.60 ± 0.42 mmol/l; p < 0.001) and post-prandial glucose (7.01 ± 1.19 to 6.47 ± 1.10; p = 0.004) decreased significantly following the intervention. Baseline HOMA-IR was elevated (3.12 ± 1.03) but did not significantly decrease (2.78 ± 1.52; p = 0.066). There were high rates of macrosomia (24.7%) and cesarean delivery (32.3%). CONCLUSIONS: Although improvements in blood glucose levels were observed among women with diet-controlled IGT and GDM, this was insufficient to significantly affect insulin resistance or perinatal outcome. Late diagnosis and treatment of IGT/GDM may have contributed to such outcomes.


Sujet(s)
Glycémie/métabolisme , Diabète gestationnel/diétothérapie , Intolérance au glucose/diétothérapie , Hyperglycémie provoquée/méthodes , Thérapie nutritionnelle/méthodes , Adulte , Femelle , Humains , Grossesse
2.
Plant Direct ; 2(4): e00057, 2018 Apr.
Article de Anglais | MEDLINE | ID: mdl-31245722

RÉSUMÉ

Weed presence early in the life cycle of maize (typically, from emergence through the 8 to 12 leaf growth stage) can reduce crop growth and yield and is known as the critical weed-free period (CWFP). Even if weeds are removed during or just after the CWFP, crop growth and yield often are not recoverable. We compared transcriptome responses of field-grown hybrid maize at V8 in two consecutive years among plants grown under weed-free and two weed-stressed conditions (weeds removed at V4 or present through V8) using RNAseq analysis techniques. Compared with weed-free plant responses, physiological differences at V8 were identified in all weed-stressed plants and were most often associated with altered photosynthetic processes, hormone signaling, nitrogen use and transport, and biotic stress responses. Even when weeds were removed at V4 and tissues sampled at V8, carbon: nitrogen supply imbalance, salicylic acid signals, and growth responses differed between the weed-stressed and weed-free plants. These underlying processes and a small number of developmentally important genes are potential targets for decreasing the maize response to weed pressure. Expression differences of several novel, long noncoding RNAs resulting from exposure of maize to weeds during the CWFP were also observed and could open new avenues for investigation into the function of these transcription units.

3.
J Environ Qual ; 46(3): 641-648, 2017 May.
Article de Anglais | MEDLINE | ID: mdl-28724110

RÉSUMÉ

Every year, the production of coal-bed natural gas in the Powder River Basin results in the discharge of large amounts of coal-bed methane water (CBMW) in Wyoming; however, no sustainable disposal methods for CBMW are currently available. A greenhouse study was conducted to evaluate the potential to use CBMW as a source of irrigation water for camelina [ (L.) Crantz]. We assessed the effects of three CBMW concentrations (0% [1:0], 50% [1:1], and 100% [0:1] tap water to CBMW) on selected soil properties, growth, seed oil, and fatty acid composition of three camelina cultivars: Blaine Creek, Ligena, and Pronghorn. The 100% CBMW reduced seed and estimated biofuel yields by 24 and 23%, respectively, but increased the oil content by 3%, relative to the control. Additionally, the 100% CBMW visibly affected soil through formation of surface crust due to elevated levels of sodium (653 mg Na kg). The 50% CBMW had no significant effects on the seed yield, estimated biofuel yield, and oil content, but the soil Na levels were still high (464 mg kg), which could pose a long-term impact on soil structure. The CBMW tended to reduce the total saturated fatty acid, but it had no significant effects on the total monounsaturated or polyunsaturated fatty acids of camelina seeds. Overall, CBMW diluted with an equal amount of good-quality water could be used to irrigate camelina in the short term. Afterward, only good-quality water would have to be used until the accumulated dissolved solids are flushed out.


Sujet(s)
Brassicaceae/croissance et développement , Méthane/composition chimique , Sol/composition chimique , Charbon , Huiles végétales
4.
G3 (Bethesda) ; 7(8): 2605-2614, 2017 08 07.
Article de Anglais | MEDLINE | ID: mdl-28592557

RÉSUMÉ

Genotypic variation at multiple loci for seed dormancy (SD) contributes to plant adaptation to diverse ecosystems. Weedy rice (Oryza sativa) was used as a model to address the similarity of SD genes between distinct ecotypes. A total of 12 quantitative trait loci (QTL) for SD were identified in one primary and two advanced backcross (BC) populations derived from a temperate ecotype of weedy rice (34.3°N Lat.). Nine (75%) of the 12 loci were mapped to the same positions as those identified from a tropical ecotype of weedy rice (7.1°N Lat.). The high similarity suggested that the majority of SD genes were conserved during the ecotype differentiation. These common loci are largely those collocated/linked with the awn, hull color, pericarp color, or plant height loci. Phenotypic correlations observed in the populations support the notion that indirect selections for the wild-type morphological characteristics, together with direct selections for germination time, were major factors influencing allelic distributions of SD genes across ecotypes. Indirect selections for crop-mimic traits (e.g., plant height and flowering time) could also alter allelic frequencies for some SD genes in agroecosystems. In addition, 3 of the 12 loci were collocated with segregation distortion loci, indicating that some gametophyte development genes could also influence the genetic equilibria of SD loci in hybrid populations. The SD genes with a major effect on germination across ecotypes could be used as silencing targets to develop transgene mitigation (TM) strategies to reduce the risk of gene flow from genetically modified crops into weed/wild relatives.


Sujet(s)
Écotype , Oryza/génétique , Dormance des plantes/génétique , Mauvaises herbes/génétique , Locus de caractère quantitatif/génétique , Climat tropical , Cartographie chromosomique , Ségrégation des chromosomes/génétique , Croisements génétiques , Génome végétal , Graines/génétique
5.
Plant Mol Biol ; 94(3): 281-302, 2017 Jun.
Article de Anglais | MEDLINE | ID: mdl-28365837

RÉSUMÉ

Leafy spurge (Euphorbia esula L.) is an herbaceous perennial weed that maintains its perennial growth habit through generation of underground adventitious buds (UABs) on the crown and lateral roots. These UABs undergo seasonal phases of dormancy under natural conditions, namely para-, endo-, and ecodormancy in summer, fall, and winter, respectively. These dormancy phases can also be induced in growth chambers by manipulating photoperiod and temperature. In this study, UABs induced into the three phases of dormancy under controlled conditions were used to compare changes in phytohormone and transcriptome profiles. Results indicated that relatively high levels of ABA, the ABA metabolite PA, and IAA were found in paradormant buds. When UABs transitioned from para- to endodormancy, ABA and PA levels decreased, whereas IAA levels were maintained. Additionally, transcript profiles associated with regulation of soluble sugars and ethylene activities were also increased during para- to endodormancy transition, which may play some role in maintaining endodormancy status. When crown buds transitioned from endo- to ecodormancy, the ABA metabolites PA and DPA decreased significantly along with the down-regulation of ABA biosynthesis genes, ABA2 and NCED3. IAA levels were also significantly lower in ecodormant buds than that of endodormant buds. We hypothesize that extended cold treatment may trigger physiological stress in endodormant buds, and that these stress-associated signals induced the endo- to ecodormancy transition and growth competence. The up-regulation of NAD/NADH phosphorylation and dephosphorylation pathway, and MAF3-like and GRFs genes, may be considered as markers of growth competency.


Sujet(s)
Euphorbia/physiologie , Dormance des plantes/physiologie , Facteur de croissance végétal/métabolisme , Protéines végétales/métabolisme , Saisons , Transcriptome , Régulation de l'expression des gènes végétaux/physiologie , Protéines végétales/génétique
6.
Plant Genome ; 10(3)2017 11.
Article de Anglais | MEDLINE | ID: mdl-29293817

RÉSUMÉ

Leafy spurge ( L.) is an invasive weed of North America and its perennial nature attributed to underground adventitious buds (UABs) that undergo seasonal cycles of para-, endo-, and ecodormancy. Recommended rates of glyphosate (∼1 kg ha) destroy aboveground shoots but plants still regenerate vegetatively; therefore, it is considered glyphosate-tolerant. However, foliar application of glyphosate at higher rates (2.2-6.7 kg ha) causes sublethal effects that induce UABs to produce stunted, bushy phenotypes. We investigated the effects of glyphosate treatment (±2.24 kg ha) on vegetative growth, phytohormone, and transcript profiles in UABs under controlled environments during one simulated seasonal cycle. Because shoots derived from UABs of foliar glyphosate-treated plants produced stunted, bushy phenotypes, we could not directly determine if these UABs transitioned through seasonally induced endo- and ecodormancy. However, transcript abundance for leafy spurge dormancy marker genes and principal component analyses suggested that UABs of foliar glyphosate-treated plants transitioned through endo- and ecodormancy. Glyphosate treatment increased shikimate abundance in UABs 7 d after treatment; however, the abundance of shikimate gradually decreased as UABs transitioned through endo- and ecodormancy. The dissipation of shikimate over time suggests that glyphosate's target site was no longer affected, but these changes did not reverse the altered phenotypes observed from UABs of foliar glyphosate-treated leafy spurge. Transcript profiles further indicated that foliar glyphosate treatment significantly affected phytohormone biosynthesis and signaling, particularly auxin transport; gibberellic acid, abscisic acid and jasmonic acid biosynthesis; ethylene responses; and detoxification and cell cycle processes in UABs. These results correlated well with the available phytohormone profiles and altered phenotypes.


Sujet(s)
Euphorbia/effets des médicaments et des substances chimiques , Glycine/analogues et dérivés , Herbicides/pharmacologie , Facteur de croissance végétal/métabolisme , Feuilles de plante/effets des médicaments et des substances chimiques , ARN messager/génétique , ARN des plantes/génétique , Euphorbia/génétique , Euphorbia/croissance et développement , Euphorbia/métabolisme , Analyse de profil d'expression de gènes , Glycine/pharmacologie , Pousses de plante/croissance et développement , Réaction de polymérisation en chaine en temps réel , Acide shikimique/métabolisme , Transduction du signal , Transcriptome ,
7.
BMC Plant Biol ; 16: 47, 2016 Feb 20.
Article de Anglais | MEDLINE | ID: mdl-26897527

RÉSUMÉ

BACKGROUND: Leafy spurge (Euphorbia esula L.) is an herbaceous weed that maintains a perennial growth pattern through seasonal production of abundant underground adventitious buds (UABs) on the crown and lateral roots. During the normal growing season, differentiation of bud to shoot growth is inhibited by physiological factors external to the affected structure; a phenomenon referred to as paradormancy. Initiation of shoot growth from paradormant UABs can be accomplished through removal of the aerial shoots (hereafter referred to as paradormancy release). RESULTS: In this study, phytohormone abundance and the transcriptomes of paradormant UABs vs. shoot-induced growth at 6, 24, and 72 h after paradormancy release were compared based on hormone profiling and RNA-seq analyses. Results indicated that auxin, abscisic acid (ABA), and flavonoid signaling were involved in maintaining paradormancy in UABs of leafy spurge. However, auxin, ABA, and flavonoid levels/signals decreased by 6 h after paradormancy release, in conjunction with increase in gibberellic acid (GA), cytokinin, jasmonic acid (JA), ethylene, and brassinosteroid (BR) levels/signals. Twenty four h after paradormancy release, auxin and ABA levels/signals increased, in conjunction with increase in GA levels/signals. Major cellular changes were also identified in UABs at 24 h, since both principal component and Venn diagram analysis of transcriptomes clearly set the 24 h shoot-induced growth apart from other time groups. In addition, increase in auxin and ABA levels/signals and the down-regulation of 40 over-represented AraCyc pathways indicated that stress-derived cellular responses may be involved in the activation of stress-induced re-orientation required for initiation of shoot growth. Seventy two h after paradormancy release, auxin, cytokinin, and GA levels/signals were increased, whereas ABA, JA, and ethylene levels/signals were decreased. CONCLUSION: Combined results were consistent with different phytohormone signals acting in concert to direct cellular changes involved in bud differentiation and shoot growth. In addition, shifts in balance of these phytohormones at different time points and stress-related cellular responses after paradormancy release appear to be critical factors driving transition of bud to shoot growth.


Sujet(s)
Euphorbia/croissance et développement , Facteur de croissance végétal/métabolisme , Euphorbia/métabolisme , Feuilles de plante/croissance et développement , Feuilles de plante/métabolisme , Pousses de plante/croissance et développement , Pousses de plante/métabolisme , Transduction du signal
8.
Early Hum Dev ; 92: 51-5, 2016 Jan.
Article de Anglais | MEDLINE | ID: mdl-26658058

RÉSUMÉ

BACKGROUND: Cardiomyopathy is a common finding in offspring of pre-gestational type 1 diabetic pregnancy. Echocardiographic and biochemical evidence of fetal cardiac dysfunction have also been reported. Studies suggest that offspring of diabetic mothers (ODM) undergo a fetal programming effect due to the hyperglycaemic intrauterine milieu which increases their risk of cardiovascular morbidity in adult life. Decreased neonatal heart rate variability (HRV) has been described in association with in-utero growth restriction, prematurity, sudden infant death syndrome and congenital heart disease. The effect of in-utero exposure to hyperglycaemia in diabetic pregnancy on neonatal HRV is unknown. AIMS: Our aim was to determine if neonatal HRV differs between normal and diabetic pregnancy. STUDY DESIGN AND SUBJECTS: This was a prospective observational study of 38 patients with pregestational type 1 diabetes and 26 controls. HRV assessment was performed using Powerlab (ADI Instruments Ltd). OUTCOME MEASURES: Heart rate variability assessment and cord blood sampling for pH and glucose were performed for all neonates. Maternal glycaemic control was assessed via measurement of glycosylated haemoglobin in each trimester in the diabetic cohort. RESULTS: Neonates of diabetic mothers had evidence of altered heart rate variability, with increased low frequency to high frequency ratio (LF: HF), suggestive of a shift towards sympathetic predominance (p<0.05). This altered HRV was significantly related to fetal acidaemia, cord blood glucose values and maternal glycaemic control during pregnancy (p<0.05). CONCLUSION: Neonates of pregestational diabetic pregnancy have altered HRV which is related to maternal hyperglycaemia, fetal acidaemia and fetal glycaemia. Exposure of the developing heart to fluctuations in maternal glycaemia with subsequent alterations in HRV may explain why infants of diabetic mothers are at greater risk of cardiovascular disease in later life.


Sujet(s)
Diabète de type 1/physiopathologie , Coeur foetal/physiologie , Rythme cardiaque , Grossesse chez les diabétiques/physiopathologie , Adulte , Études cas-témoins , Femelle , Coeur foetal/physiopathologie , Humains , Nouveau-né , Mâle , Grossesse
9.
PLoS One ; 10(9): e0137215, 2015.
Article de Anglais | MEDLINE | ID: mdl-26368559

RÉSUMÉ

OBJECTIVE: Gender plays a role in the development of a number of cardiovascular and metabolic diseases and it has been suggested that females may be more insulin resistant in utero. We sought to assess the relationship between infant gender and insulin resistance in a large pregnancy cohort. STUDY DESIGN: This is a secondary analysis of a cohort from the ROLO randomized control trial of low GI diet in pregnancy. Serum insulin, glucose and leptin were measured in early pregnancy and at 28 weeks. At delivery cord blood C-peptide and leptin were measured. A comparison of maternal factors, fetal biometry, insulin resistance and leptin was made between male and female offspring. A multivariate regression model was built to account for the possible effects of maternal BMI, birthweight and original study group assignment on findings. RESULTS: A total of 582 women were included in this secondary analysis, of whom 304 (52.2%) gave birth to male and 278 (47.8%) gave birth to female infants. Compared to male infants at birth, female infants were significantly lighter, (3945 ± 436 vs. 4081± 549g, p<0.001), shorter in length (52.36 ± 2.3 vs. 53.05 ± 2.4cm, p<0.001) and with smaller head circumferences (35.36 ± 1.5 vs. 36.10 ± 1.1cm, p<0.001) than males. On multiple regression analysis, women pregnant with female fetuses were less insulin resistant in early pregnancy, i.e. had lower HOMA indices (B = -0.19, p = 0.01). Additionally female fetuses had higher concentrations of both cord blood leptin and C-peptide at birth when compared to male offspring (B = 0.38, p<0.001 and B = 0.31, p = 0.03 respectively). CONCLUSION: These findings suggest gender is a risk factor for insulin resistance in-utero. Additionally, carrying a female fetus decreases the risk of insulin resistance in the mother, from as early as the first trimester.


Sujet(s)
Peptide C/sang , Sang foetal/composition chimique , Développement foetal/physiologie , Insulinorésistance , Leptine/sang , Poids de naissance , Indice de masse corporelle , Femelle , Humains , Nourrisson , Mâle , Grossesse , Facteurs de risque , Facteurs sexuels
10.
BMC Genomics ; 16: 395, 2015 May 19.
Article de Anglais | MEDLINE | ID: mdl-25986459

RÉSUMÉ

BACKGROUND: Leafy spurge (Euphorbia esula) is a perennial weed that is considered glyphosate tolerant, which is partially attributed to escape through establishment of new vegetative shoots from an abundance of underground adventitious buds. Leafy spurge plants treated with sub-lethal concentrations of foliar-applied glyphosate produce new vegetative shoots with reduced main stem elongation and increased branching. Processes associated with the glyphosate-induced phenotype were determined by RNAseq using aerial shoots derived from crown buds of glyphosate-treated and -untreated plants. Comparison between transcript abundance and accumulation of shikimate or phytohormones (abscisic acid, auxin, cytokinins, and gibberellins) from these same samples was also done to reveal correlations. RESULTS: Transcriptome assembly and analyses confirmed differential abundance among 12,918 transcripts (FDR ≤ 0.05) and highlighted numerous processes associated with shoot apical meristem maintenance and stem growth, which is consistent with the increased number of actively growing meristems in response to glyphosate. Foliar applied glyphosate increased shikimate abundance in crown buds prior to decapitation of aboveground shoots, which induces growth from these buds, indicating that 5-enolpyruvylshikimate 3-phosphate (EPSPS) the target site of glyphosate was inhibited. However, abundance of shikimate was similar in a subsequent generation of aerial shoots derived from crown buds of treated and untreated plants, suggesting EPSPS is no longer inhibited or abundance of shikimate initially observed in crown buds dissipated over time. Overall, auxins, gibberellins (precursors and catabolites of bioactive gibberellins), and cytokinins (precursors and bioactive cytokinins) were more abundant in the aboveground shoots derived from glyphosate-treated plants. CONCLUSION: Based on the overall data, we propose that the glyphosate-induced phenotype resulted from complex interactions involving shoot apical meristem maintenance, hormone biosynthesis and signaling (auxin, cytokinins, gibberellins, and strigolactones), cellular transport, and detoxification mechanisms.


Sujet(s)
Euphorbia , Glycine/analogues et dérivés , Facteur de croissance végétal/métabolisme , Tiges de plante/croissance et développement , Transcriptome/effets des médicaments et des substances chimiques , Acide chorismique/biosynthèse , Euphorbia/effets des médicaments et des substances chimiques , Euphorbia/génétique , Euphorbia/croissance et développement , Glycine/pharmacologie , Herbicides/pharmacologie , Pousses de plante/effets des médicaments et des substances chimiques , Pousses de plante/génétique , Pousses de plante/métabolisme , Tiges de plante/effets des médicaments et des substances chimiques , Tiges de plante/génétique , Tiges de plante/métabolisme , Analyse de séquence d'ARN , Acide shikimique/métabolisme , Transduction du signal/effets des médicaments et des substances chimiques ,
11.
J Agric Food Chem ; 63(16): 4042-9, 2015 Apr 29.
Article de Anglais | MEDLINE | ID: mdl-25853587

RÉSUMÉ

Sesquiterpene lactones in sunflowers, Helianthus spp., are important to interactions with pathogens, weeds, and insects. Across a broad range of Helianthus annuus, differences in composition of sesquiterpene lactones extracted from disc florets were found between wild and cultivated sunflowers and also between distinct groups of inbreds used to produce sunflower hybrids. Discriminant function analysis showed the presence and relative abundance of argophyllone B, niveusin B, and 15-hydroxy-3-dehydrodesoxyfruticin were usually (75%) effective at classifying wild sunflowers, cultivated inbreds, and hybrids. Argophyllone B reduced the larval mass of the sunflower moth, Homeosoma electellum, by >30%, but only at a dose greater than that found in florets. Low doses of mixed extracts from cultivated florets produced a similar (≈40%) reduction in larval mass, suggesting combinations of sesquiterpene lactones act additively. Although the results support a role for sesquiterpene lactones in herbivore defense of cultivated sunflowers, additional information is needed to use these compounds purposefully in breeding.


Sujet(s)
Helianthus/composition chimique , Lactones/pharmacologie , Papillons de nuit/effets des médicaments et des substances chimiques , Extraits de plantes/pharmacologie , Sesquiterpènes/pharmacologie , Animaux , Helianthus/classification , Helianthus/croissance et développement , Lactones/composition chimique , Structure moléculaire , Extraits de plantes/composition chimique , Sesquiterpènes/composition chimique
12.
Am J Obstet Gynecol ; 212(4): 496.e1-11, 2015 Apr.
Article de Anglais | MEDLINE | ID: mdl-25687568

RÉSUMÉ

OBJECTIVE: Probiotics are live microorganisms that may confer health benefits on the host. Recent trials of probiotic use among healthy pregnant women demonstrate potential for improved glycemic control. The aim of this study was to investigate the effects of a probiotic capsule intervention on maternal metabolic parameters and pregnancy outcome among women with gestational diabetes. STUDY DESIGN: This double-blind placebo-controlled randomized trial recruited pregnant women with a new diagnosis of gestational diabetes or impaired glucose tolerance following a 3-hour 100-g glucose tolerance test. Women were randomized to a daily probiotic (Lactobacillus salivarius UCC118) or placebo capsule from diagnosis until delivery. Fasting blood samples were collected at baseline and 4-6 weeks after capsule commencement for analysis of glucose, insulin, c-peptide, and lipids. The primary outcome was difference in fasting glucose postintervention, first analyzed on an intention-to-treat basis and followed by per-protocol analysis that excluded women commenced on pharmacological therapy (insulin or metformin). Secondary outcomes were changes in insulin, c-peptide, homeostasis model assessment and lipids, requirement for pharmacological therapy, and neonatal anthropometry. RESULTS: Of 149 women recruited and randomized, there were no differences between the probiotic and placebo groups in postintervention fasting glucose (4.65 ± 0.49 vs 4.65 ± 0.53 mmol/L; P = 373), requirement for pharmacological therapy (17% vs 14%; P = .643), or birthweight (3.57 ± 0.64 vs 3.60 ± 0.57 kg; P = .845). Among 100 women managed with diet and exercise alone, fasting plasma glucose decreased significantly within both the probiotic (4.76 ± 0.45 to 4.57 ± 0.42 mmol/L; P < .001) and placebo (4.85 ± 0.58 to 4.58 ± 0.45 mmol/L; P < .001) groups, but the levels between groups did not differ (P = .316). The late gestation-related rise in total and low-density lipoprotein (LDL) cholesterol was attenuated in the probiotic vs the placebo group (+0.27 ± 0.48 vs +0.50 ± 0.52 mmol/L total cholesterol, P = .031; +0.08 ± 0.51 vs +0.31 ± 0.45 mmol/L LDL cholesterol, P = .011). No differences were noted between groups in other metabolic parameters or pregnancy outcome. CONCLUSION: A probiotic capsule intervention among women with abnormal glucose tolerance had no impact on glycemic control. The observed attenuation of the normal pregnancy-induced rise in total and LDL cholesterol following probiotic treatment requires further investigation, particularly in this obstetric group at risk of future metabolic syndrome.


Sujet(s)
Diabète gestationnel/thérapie , Lactobacillus , Probiotiques/usage thérapeutique , Adulte , Marqueurs biologiques/sang , Glycémie/métabolisme , Peptide C/sang , Cholestérol/sang , Diabète gestationnel/sang , Méthode en double aveugle , Femelle , Humains , Nouveau-né , Insuline/sang , Analyse en intention de traitement , Grossesse , Issue de la grossesse , Résultat thérapeutique
13.
BMC Plant Biol ; 14: 216, 2014 Aug 12.
Article de Anglais | MEDLINE | ID: mdl-25112962

RÉSUMÉ

BACKGROUND: Leafy spurge (Euphorbia esula L.) is a herbaceous perennial weed and dormancy in both buds and seeds is an important survival mechanism. Bud dormancy in leafy spurge exhibits three well-defined phases of para-, endo- and ecodormancy; however, seed dormancy for leafy spurge is classified as physiological dormancy that requires after-ripening and alternating temperature for maximal germination. Overlaps in transcriptome profiles between different phases of bud and seed dormancy have not been determined. Thus, we compared various phases of dormancy between seeds and buds to identify common genes and molecular processes, which should provide new insights about common regulators of dormancy. RESULTS: Cluster analysis of expression profiles for 201 selected genes indicated bud and seed samples clustered separately. Direct comparisons between buds and seeds are additionally complicated since seeds incubated at a constant temperature of 20°C for 21 days (21d C) could be considered paradormant (Para) because seeds may be inhibited by endosperm-generated signals, or ecodormant (Eco) because seeds germinate after being subjected to alternating temperature of 20:30°C. Since direct comparisons in gene expression between buds and seeds were problematic, we instead examined commonalities in differentially-expressed genes associated with different phases of dormancy. Comparison between buds and seeds ('Para to Endo buds' and '21d C to 1d C seeds'), using endodormant buds (Endo) and dormant seeds (1d C) as common baselines, identified transcripts associated with cell cycle (HisH4), stress response/transcription factors (ICE2, ERFB4/ABR1), ABA and auxin response (ABA1, ARF1, IAA7, TFL1), carbohydrate/protein degradation (GAPDH_1), and transport (ABCB2). Comparison of transcript abundance for the 'Eco to Endo buds' and '21d C to 1d C seeds' identified transcripts associated with ABA response (ATEM6), auxin response (ARF1), and cell cycle (HisH4). These results indicate that the physiological state of 21d C seeds is more analogous to paradormant buds than that of ecodormant buds. CONCLUSION: Combined results indicate that common molecular mechanisms associated with dormancy transitions of buds and seeds involve processes associated with ABA and auxin signaling and transport, cell cycle, and AP2/ERF transcription factors or their up-stream regulators.


Sujet(s)
Euphorbia/métabolisme , Dormance des plantes , Analyse de regroupements , Euphorbia/croissance et développement , Expression des gènes , Acides indolacétiques/métabolisme , Réaction de polymérisation en chaine en temps réel
14.
Br J Nutr ; 112(4): 583-9, 2014 Aug 28.
Article de Anglais | MEDLINE | ID: mdl-24896237

RÉSUMÉ

The present study is a secondary analysis of the ROLO study, a randomised control trial of a low-glycaemic index (GI) diet in pregnancy to prevent the recurrence of fetal macrosomia. The objectives of the present study were to identify which women are most likely to respond to a low-GI dietary intervention in pregnancy with respect to three outcome measures: birth weight; maternal glucose intolerance; gestational weight gain (GWG). In early pregnancy, 372 women had their mid-upper arm circumference recorded and BMI calculated. Concentrations of glucose, insulin and leptin were measured in early pregnancy and at 28 weeks. At delivery, infant birth weight was recorded and fetal glucose, C-peptide and leptin concentrations were measured in the cord blood. Women who benefited in terms of infant birth weight were shorter, with a lower education level. Those who maintained weight gain within the GWG guidelines were less overweight in both their first and second pregnancies, with no difference being observed in maternal height. Women who at 28 weeks of gestation developed glucose intolerance, despite the low-GI diet, had a higher BMI and higher glucose concentrations in early pregnancy with more insulin resistance. They also had significantly higher-interval pregnancy weight gain. For each analysis, women who responded to the intervention had lower leptin concentrations in early pregnancy than those who did not. These findings suggest that the maternal metabolic environment in early pregnancy is important in determining later risks of excessive weight gain and metabolic disturbance, whereas birth weight is mediated more by genetic factors. It highlights key areas, which warrant further interrogation before future pregnancy intervention studies, in particular, maternal education level and inter-pregnancy weight gain.


Sujet(s)
Adiposité , Régime pauvre en glucides , Intolérance au glucose/prévention et contrôle , Indice glycémique , Insulinorésistance , Phénomènes physiologiques nutritionnels maternels , Complications de la grossesse/prévention et contrôle , Adulte , Poids de naissance , Indice de masse corporelle , Études de cohortes , Régime pauvre en glucides/effets indésirables , Niveau d'instruction , Femelle , Sang foetal , Macrosomie foetale/étiologie , Macrosomie foetale/prévention et contrôle , Intolérance au glucose/sang , Intolérance au glucose/métabolisme , Intolérance au glucose/physiopathologie , Humains , Insuline/sang , Leptine/sang , Éducation du patient comme sujet , Grossesse , Complications de la grossesse/sang , Complications de la grossesse/métabolisme , Complications de la grossesse/physiopathologie , Prévention secondaire , Prise de poids
15.
Early Hum Dev ; 90(6): 271-4, 2014 Jun.
Article de Anglais | MEDLINE | ID: mdl-24703297

RÉSUMÉ

BACKGROUND: Interrogation of the association between leptin, insulin resistance and fetal growth may provide a biological link for the fetal programming of later metabolic health. AIMS: Our aim was to clarify the relationship between maternal and fetal leptin, insulin resistance and fetal growth. STUDY DESIGN: Maternal leptin, glucose and insulin were measured in early pregnancy and at 28weeks and the HOMA index calculated. At 34weeks, ultrasound scan assessed fetal weight and adiposity (abdominal wall width). At delivery birthweight was recorded and cord blood analyzed for fetal c-peptide and leptin. Analysis was performed using a multivariate linear regression model. SUBJECTS: 574 non-diabetic pregnant women. OUTCOME MEASURES: Fetal growth and maternal and fetal insulin resistance. RESULTS: On multivariate analysis a relationship was identified between maternal and fetal leptin concentrations at each time point and maternal body mass index. Maternal leptin was related to insulin resistance in early pregnancy (ß=0.15, p=0.02) and at 28week gestation (ß=0.27, p<0.001). Fetal insulin resistance correlated with maternal leptin in early pregnancy (ß=0.17, p=0.004); at 28weeks (ß=0.12, p=0.05), and with leptin in cord blood (r=0.28, p<0.001). Fetal weight at 34weeks was related to maternal leptin in early pregnancy (ß=0.16, p=0.02). Both maternal and fetal leptin correlated with infant size at birth (ß=0.12, p=0.07 in early pregnancy, ß=0.21, p=0.004 in cord blood), independent of all other outcome measures. CONCLUSION: Our findings have confirmed that in a non-diabetic cohort there is a link between maternal and fetal leptin and insulin resistance. We also established a link between maternal leptin in early pregnancy and both fetal and neonatal size. These results add to the growing body of evidence suggesting a role for leptin in the fetal programming of childhood obesity and metabolic dysfunction.


Sujet(s)
Développement foetal , Insulinorésistance , Leptine/sang , Adiposité , Adulte , Poids de naissance , Glycémie , Indice de masse corporelle , Femelle , Sang foetal/métabolisme , Poids du foetus , Humains , Nouveau-né , Analyse multifactorielle , Grossesse , Études prospectives , Échographie prénatale
16.
Obesity (Silver Spring) ; 22(7): 1594-600, 2014 Jul.
Article de Anglais | MEDLINE | ID: mdl-24715415

RÉSUMÉ

OBJECTIVE: To compare maternal characteristics, obstetric outcomes and insulin resistance in a cohort of women subdivided into those who did and those who did not exceed the Institute of Medicine (IOM) gestational weight gain guidelines. METHODS: This is a prospective study of 621 women without diabetes. Concentrations of glucose, insulin and leptin were measured in early pregnancy and at 28 weeks. Ultrasound at 34 weeks assessed fetal anthropometry including abdominal wall width (AAW). At delivery birthweight was recorded and fetal glucose, C-peptide and leptin measured in cord blood. Insulin resistance was calculated using the HOMA equation. Outcomes in those who did and did not exceed IOM guidelines were compared. RESULTS: Overall, 267 women (43%) exceeded IOM guidelines and 354 (57%) did not. On 34-week ultrasound women with excessive weight gain had higher fetal weights (2681 ± 356 g vs. 2574 ± 331, P = 0.001) and fetal adiposity (AAW) (5.29 ± 1.3 vs. 4.8 ± 1.2, P = 0.001). Infant birthweight and birthweight centiles were also higher in those who exceeded the guidelines. There was no difference between the two groups in maternal insulin resistance in early pregnancy, but by 28 weeks those with excessive weight gain had higher maternal HOMA indices and higher maternal leptin concentrations. CONCLUSION: Excessive maternal gestational weight gain has significant implications for infant growth and adiposity, with potential implications for later adult health.


Sujet(s)
Adiposité/physiologie , Poids de naissance/physiologie , Sang foetal/métabolisme , Insuline/sang , Leptine/sang , Grossesse/physiologie , Prise de poids/physiologie , Adulte , Indice de masse corporelle , Peptide C/métabolisme , Protéine C-réactive/analyse , Femelle , Humains , Nouveau-né , Études prospectives , États-Unis
17.
Reprod Sci ; 21(11): 1378-81, 2014 Nov.
Article de Anglais | MEDLINE | ID: mdl-24642719

RÉSUMÉ

This is a secondary analysis of 621 women in ROLO study, a randomized control trial of low glycemic index (GI) diet in pregnancy to prevent the recurrence of macrosomia, which aims to assess the effect of the diet on maternal and fetal insulin resistance, leptin, and markers of inflammation. In early pregnancy and at 28 weeks, serum was analyzed for insulin, leptin, tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6). At delivery, cord blood concentrations of leptin, TNF-α, IL-6, and C-peptide were recorded. We found no difference between those who did or did not receive low GI advice with respect to the concentrations of any marker in early pregnancy, at 28 weeks or in cord blood. Women in the intervention arm of the study did have a lower overall rise in insulin concentrations from early pregnancy to 28 weeks gestation, P = .04. Of the women in the intervention arm, 20% were in the highest quartile for insulin change (28-week insulin - insulin at booking) compared to 29% of controls (P = .02). In conclusion, a low GI diet in pregnancy has little effect on leptin and markers of inflammation although an attenuated response to the typical increase in insulin resistance seen in pregnancy with advancing gestation was seen in those who received the low GI advice.


Sujet(s)
Régime pauvre en glucides , Sang foetal/métabolisme , Macrosomie foetale/prévention et contrôle , Indice glycémique , Médiateurs de l'inflammation/sang , Insulinorésistance , Leptine/sang , Phénomènes physiologiques nutritionnels maternels , Marqueurs biologiques/sang , Peptide C/sang , Femelle , Âge gestationnel , Humains , Interleukine-6/sang , État nutritionnel , Grossesse , Facteur de nécrose tumorale alpha/sang
18.
Plant Mol Biol ; 81(6): 577-93, 2013 Apr.
Article de Anglais | MEDLINE | ID: mdl-23436173

RÉSUMÉ

Leafy spurge is a model for studying well-defined phases of dormancy in underground adventitious buds (UABs) of herbaceous perennial weeds, which is a primary factor facilitating their escape from conventional control measures. A 12-week ramp down in both temperature (27 â†’ 10 °C) and photoperiod (16 â†’ 8 h light) is required to induce a transition from para- to endo-dormancy in UABs of leafy spurge. To evaluate the effects of photoperiod and temperature on molecular networks of UABs during this transition, we compared global transcriptome data-sets obtained from leafy spurge exposed to a ramp down in both temperature and photoperiod (RDtp) versus a ramp down in temperature (RDt) alone. Analysis of data-sets indicated that transcript abundance for genes associated with circadian clock, photoperiodism, flowering, and hormone responses (CCA1, COP1, HY5, MAF3, MAX2) preferentially increased in endodormant UABs. Gene-set enrichment analyses also highlighted metabolic pathways involved in endodormancy induction that were associated with ethylene, auxin, flavonoids, and carbohydrate metabolism; whereas, sub-network enrichment analyses identified hubs (CCA1, CO, FRI, miR172A, EINs, DREBs) of molecular networks associated with carbohydrate metabolism, circadian clock, flowering, and stress and hormone responses. These results helped refine existing models for the transition to endodormancy in UABs of leafy spurge, which strengthened the roles of circadian clock associated genes, DREBs, COP1-HY5, carbohydrate metabolism, and involvement of hormones (ABA, ethylene, and strigolactones). We further examined the effects of ethylene by application of 1-aminocyclopropane-1-carboxylate (ACC) to paradormant plants without a ramp down treatment. New vegetative growth from UABs of ACC-treated plants resulted in a dwarfed phenotype that mimicked the growth response in RDtp-induced endodormant UABs. The results of this study provide new insights into dormancy regulation suggesting a short-photoperiod treatment provides an additive cross-talk effect with temperature signals that may impact ethylene's effect on AP2/ERF family members.


Sujet(s)
Éthylènes/biosynthèse , Euphorbia/croissance et développement , Photopériode , Feuilles de plante/croissance et développement , Température , Acide abscissique/biosynthèse , Acide abscissique/génétique , Métabolisme glucidique , Horloges circadiennes , Rythme circadien , Bases de données génétiques , Euphorbia/génétique , Euphorbia/métabolisme , Flavonoïdes/biosynthèse , Flavonoïdes/génétique , Fleurs/croissance et développement , Fleurs/métabolisme , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes végétaux , Gènes de plante , Acides indolacétiques/métabolisme , Modèles biologiques , Phénotype , Phosphorylation , Facteur de croissance végétal/biosynthèse , Facteur de croissance végétal/génétique , Feuilles de plante/génétique , Feuilles de plante/métabolisme , Transcriptome
19.
Am J Perinatol ; 30(8): 661-4, 2013 Sep.
Article de Anglais | MEDLINE | ID: mdl-23271385

RÉSUMÉ

OBJECTIVE: This study set out to describe the incidence, mortality rates, and treatment of eclampsia over a 30-year period in a large urban population. STUDY DESIGN: A detailed report of all pregnancies delivered in the Dublin area from 1977 to 2006 was reviewed for incidence, mortality, and treatment of eclampsia. Almost all pregnancies in this area are managed at one of three major obstetric hospitals. All offer comprehensive antenatal care and operate a restrictive policy to magnesium sulfate prophylaxis, in which MgSO4 is reserved for patients with severe preeclampsia or who have already had an eclamptic seizure. RESULTS: During the 30-year study period, there were a total of 626,929 deliveries. Of the 247 cases of eclampsia (3.9/10,000 deliveries) and four maternal deaths (0.63/100,000 deliveries) attributed to eclampsia, none received MgSO4. The mortality rate due to eclampsia was 1.6% (4/247). The use of MgSO4 increased significantly from 11% (13/115) in the first decade of the study to 88.1% (67/76) in the last decade (p < 0.001). The incidence of eclampsia decreased from 5.4/10,000 in the first decade to 3.5/10,000 in the final decade of the study (p < 0.0001). CONCLUSION: Over the study period, MgSO4 has become the leading antiseizure medication used, and this has led to a significant decrease in rates of eclampsia.


Sujet(s)
Anticonvulsivants/usage thérapeutique , Éclampsie/épidémiologie , Sulfate de magnésium/usage thérapeutique , Mortalité maternelle/tendances , Pré-éclampsie/traitement médicamenteux , Études de cohortes , Éclampsie/traitement médicamenteux , Éclampsie/thérapie , Femelle , Humains , Incidence , Irlande/épidémiologie , Grossesse , Études rétrospectives , Centres de soins tertiaires , Population urbaine
20.
J Plant Physiol ; 170(6): 539-47, 2013 Apr 15.
Article de Anglais | MEDLINE | ID: mdl-23261266

RÉSUMÉ

Seed dormancy is an important stage in the life cycle of many non-domesticated plants, often characterized by the temporary failure to germinate under conditions that normally favor the process. Pre-treating dormant imbibed seeds at a constant temperate accelerated germination of leafy spurge seeds under alternating temperatures. However, dormant seeds will also germinate without a pre-treatment, albeit at a much slower rate, which gives rise to longer periods of imbibition before germination. Transcriptome analyses on seeds exposed to prolonged imbibition highlighted pathways associated with phenylpropanoid biosynthesis and interacting networks of genes involved in plant defense. In addition to the many pathways associated with phenylpropanoid biosynthesis enriched with down-regulated genes upon germination, there were also numerous pathways enriched with up-regulated genes associated with energy metabolism, such as glycolysis. Transcriptome data further suggest that metabolism and signaling by the plant hormones ethylene, gibberellin, and abscisic acid are involved in the developmental transition from dormancy to germination. More specifically, sub-network enrichment analysis identified ABI3 as a central hub of a sub-network at germination including several down-regulated genes such as DELLA (i.e., RGL2), which represses gibberellin signaling processes required for germination. The 595-fold increase in the expression of ACC oxidase (ACO4) at germination also suggests an important role for ethylene biosynthesis in germinating leafy surge seeds. Furthermore, the 10-578-fold difference in expression of many genes such as HY5 and Histone H3 between two populations at germination, which were treated with and without a constant temperature germination-enhancing pretreatment, revealed disparate impacts on various biosynthetic, growth, signaling, and response processes. Overall, our results indicate a constant temperature pretreatment (20°C for 21d) is not required for germination of leafy spurge seeds at an alternating temperature. However, the presence or absence of the pretreatment does affect the rate of germination and the germination transcriptional programs.


Sujet(s)
Euphorbia/génétique , Régulation de l'expression des gènes végétaux , Germination , Protéines végétales/physiologie , Transduction du signal , Transcriptome , Euphorbia/croissance et développement , Euphorbia/métabolisme , Analyse de profil d'expression de gènes , Séquençage par oligonucléotides en batterie , Réaction de polymérisation en chaine en temps réel , Plant/génétique , Température
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