Changes in plant growth, Cd partitioning and xylem sap composition in two sunflower cultivars exposed to low Cd concentrations in hydroponics.

This study characterizes sunflower response to the levels of Cd encountered in moderately Cd-polluted soils. Two sunflower cultivars differing in their ability to sequestrate Cd in roots were exposed to low concentrations of Cd (0.5 nM or 100 nM) in hydroponics and sampled after 18 days (258 degree-days) when ten leaves were fully expanded. Plant growth, Cd uptake and partitioning among organs were monitored along with the ionomic (ICP-MS) and the metabolic (1H-NMR) composition of the xylem sap. Sunflower tolerance to Cd differed between the two cultivars. The cultivar with the highest ability to sequestrate Cd in roots (Kapllan) was more tolerant to Cd than the one with the lowest ability (ES RICA). The 23% penalization of plant growth observed at 100 nM in cultivar ES RICA was associated with reduced xylem loading fluxes of soluble sugars, perhaps pointing to disruption of carbohydrate metabolism. Retention of Cd in the stem was higher at 100 nM than at 0.5 nM in the Cd-sensitive cultivar ES RICA, which can be seen as a sunflower strategy to restrict the amount of Cd delivered to the leaves under Cd stress. No direct connection was found between the speciation of Cd in the xylem sap and the Cd translocation efficiency, although significant changes in the free ionic fraction of Cd were observed between the two cultivars at 0.5 nM. The relevance of these results in promoting the use of sunflower in phytomanagement of Cd-polluted soils is discussed.

Rat feeding trials: A comprehensive assessment of contaminants in both genetically modified maize and resulting pellets.

We analyzed a comprehensive set of contaminants in MON810 and NK603 genetically modified (GM) maize, and their non-GM counterparts, used in a rat feeding study (the GMO90 + project). Both the maize grains and the manufactured pellets were characterized. Only minor differences in contaminant levels between GM and corresponding non-GM harvests were evidenced. Fumonisin and deoxynivalenol mycotoxins were the pollutants present in the highest amounts, with concentrations that were however largely below acceptance reference values. Our data reporting slightly lower levels of fumonisin in MON810 compared to its non-GM counterpart corroborate the lower susceptibility of insect resistant Bt maize to fumonisin-producing fungi. Traces of glyphosate (0.016 mg/kg) were evidenced in grains from NK603 treated crops. Regarding the pellets, analysis of more than 650 potentially toxic substances revealed low amounts of various mycotoxins, pesticides and heavy metals. Concentrations of contaminants quantified in the pellets were however far below the maximum level of residues values set by regulatory agencies, and no substantial differences in contaminants between GM and non-GM pellets were observed. Moreover, when comparing the contamination status of grains and pellets, we demonstrate yet again that characterizing the grains is actually not sufficient to foresee the quality of the produced pellets.

Prospective follow-up of a cohort of preterm infants<33 WG receiving ketamine for tracheal intubation in the delivery room: Neurological outcome at 1 and 2 years.

OBJECTIVE: Although ketamine analgesia is effective in reducing pain and facilitating the tracheal intubation of newborns in the delivery room, no data on the neurological effects of this treatment are available. This study compared the neurodevelopmental outcomes at 2 years of age in a cohort of preterm newborns having received ketamine prior to tracheal intubation at birth (the ketamine group) and in a control group. METHODS: We included newborns delivered at less than 33 weeks gestational age (WGA) having undergone tracheal intubation at birth. The Ages and Stages Questionnaire (ASQ) was completed at 1 and 2 years of age. The development quotient (DQ) was calculated from the revised Brunet-Lezine score assessed at a corrected age of 2 years. RESULTS: There were no statistically significant differences between the ketamine group (n=54 at 1 year and n=51 at 2 years) and the control group (n=16 at 1 and 2 years) in terms of the mean±standard deviation DQ at the age of 2 (98±12 vs. 103±9, respectively; P=0.17) and the ASQ score at the age of 2 (221±44 vs. 230±39, respectively; P=0.55). DISCUSSION: This prospective cohort of 51 preterm newborns having received ketamine at birth did not reveal any differences in terms of neurological development at the age of 2 (relative to a control group and the literature data). These preliminary results must be confirmed in a randomized trial with longer follow-up.

NMRProcFlow: a graphical and interactive tool dedicated to 1D spectra processing for NMR-based metabolomics.

INTRODUCTION: Concerning NMR-based metabolomics, 1D spectra processing often requires an expert eye for disentangling the intertwined peaks. OBJECTIVES: The objective of NMRProcFlow is to assist the expert in this task in the best way without requirement of programming skills. METHODS: NMRProcFlow was developed to be a graphical and interactive 1D NMR (1H & 13C) spectra processing tool. RESULTS: NMRProcFlow (http://nmrprocflow.org), dedicated to metabolic fingerprinting and targeted metabolomics, covers all spectra processing steps including baseline correction, chemical shift calibration and alignment. CONCLUSION: Biologists and NMR spectroscopists can easily interact and develop synergies by visualizing the NMR spectra along with their corresponding experimental-factor levels, thus setting a bridge between experimental design and subsequent statistical analyses.

Genetic dissection of fruit quality traits in the octoploid cultivated strawberry highlights the role of homoeo-QTL in their control.

Fruit quality traits are major breeding targets in the Rosaceae. Several of the major Rosaceae species are current or ancient polyploids. To dissect the inheritance of fruit quality traits in polyploid fleshy fruit species, we used a cultivated strawberry segregating population comprising a 213 full-sibling F1 progeny from a cross between the variety 'Capitola' and the genotype 'CF1116'. We previously developed the most comprehensive strawberry linkage map, which displays seven homoeology groups (HG), including each four homoeology linkage groups (Genetics 179:2045-2060, 2008). The map was used to identify quantitative trait loci (QTL) for 19 fruit traits related to fruit development, texture, colour, anthocyanin, sugar and organic acid contents. Analyses were carried out over two or three successive years on field-grown plants. QTL were detected for all the analysed traits. Because strawberry is an octopolyploid species, QTL controlling a given trait and located at orthologous positions on different homoeologous linkage groups within one HG are considered as homoeo-QTL. We found that, for various traits, about one-fourth of QTL were putative homoeo-QTL and were localised on two linkage groups. Several homoeo-QTL could be detected the same year, suggesting that several copies of the gene underlying the QTL are functional. The detection of some other homoeo-QTL was year-dependent. Therefore, changes in allelic expression could take place in response to environmental changes. We believe that, in strawberry as in other polyploid fruit species, the mechanisms unravelled in the present study may play a crucial role in the variations of fruit quality.

[Experience with levetiracetam in the treatment of childhood refractory epilepsy]. / Utilisation du lévétiracétam (LEV) dans le traitement des épilepsies réfractaires de l'enfant : expérience du service de neuropédiatrie du CHU d'Amiens en France.

INTRODUCTION: In young children presenting drug-resistant epilepsy, the number of approved antiepileptic drugs is limited. Levetiracetam (LEV) is one of the most recent antiepileptic drugs (AED) introduced on the market and data on its effectiveness and tolerance in children are scarce. PATIENTS AND METHODS: The objective of this retrospective study was to report our experience with the use of levetiracetam as an adjuvant therapy in a population of 42 children presenting a drug-resistant epilepsy. The study was conducted over a 5-year-period (from 1 January 2004 to 30 June 2007). RESULTS: The patients' mean age was 10.8 years (range, 2.1-19 years). The mean duration of epilepsy was 6.6 years (range, 1.5-19 years). After the administration of LEV, 10 patients (23.8%) became seizure-free and 16 (38.1%) had more than 50% seizure reduction. A reduction of less than 50% was observed in 13 patients (31%). Three patients (7.1%) presented an increase in seizure frequency. The effectiveness of LEV was similar in partial and generalized epilepsy. LEV was well tolerated by these patients. The main adverse effects were anorexia, asthenia, and behavioral disorders, and drowsiness was encountered in 17% of the patients. All persistent adverse events were noted. In children under 4 years of age, LEV was particularly well tolerated. CONCLUSION: This study confirms the effectiveness and tolerance of LEV used as an adjuvant therapy in children presenting drug-resistant epilepsy, particularly in the very young ones.

[Familial and non-familial benign infantile seizures: A homogeneous entity?]. / Convulsions infantiles bénignes familiales et non familiales : une entité homogène ?

Among the epileptic syndromes occurring during infancy, which are mostly non-idiopathic and associated with a poor prognosis, benign infantile convulsions are characterized by a favourable evolution. This work aims to analyse and compare the clinical, EEG and outcome characteristics of familial benign infantile convulsions (FBIC) and non-familial benign infantile convulsions (NFBIC). This is a retrospective study, conducted between 1988 and 2008, in 40 infants who presented benign infantile seizures during the two first years of life. All of them had no personal history, normal psychomotor development, normal neurological examinations, no abnormalities on biological and radiological investigations and a favourable outcome. In 14 cases, there was a familial history of familial benign infantile convulsions. However, among the 26 cases with non-familial benign infantile convulsions, 11 children had a familial history of other epileptic syndrome. That may suggest a genetic familial susceptibility. In the two groups, the clinical features and the electroencephalography were similar. The seizures had short duration and occurred most often in clusters. Twenty-nine children had secondarily generalized partial seizures and 11 infants had generalized seizures but a focal onset cannot be excluded. The antiepileptic drugs allowed rapid resolution of seizures. One child necessitated a prolonged antiepileptic treatment. In the other cases, seizures cured in the first year without recurrence of seizures after treatment discontinuation. The evolution was characterised in five children by a later occurrence of dystonia. This subgroup was described as infantile convulsion and choreoathetosis syndrome (ICCA). Benign infantile convulsions are probably an underestimated epileptic syndrome. The diagnosis is relatively easy in the familial forms with dominant autosomal transmission. In contrast, in sporadic forms, the diagnosis can be confirmed only by the evolution. The good prognosis must be tempered by the subsequent onset of dystonia consisted in the ICCA syndrome and justifies a prolonged follow-up.

[Infratentorial ischemic stroke in children: Three case reports]. / Accidents vasculaires cérébraux de la fosse postérieure chez l'enfant : à propos de trois cas.

Ischemic stroke is rare in children, most of which occur in the supratentorial brain, and infratentorial infarcts are very rare. Some clinical manifestations may be similar but others such as ataxia and cranial nerve palsy are more specific. Vertebral artery dissection is the most frequent cause of stroke in the vertebrobasilar territory, but the cause most often remains unknown in children. We report three cases of infratentorial stroke in children. The first observation concerns a 4-year-old boy brought to medical attention because left hemicorporal motor deficit associated with ataxia following a minor cranial traumatism. While computed tomography (CT) of the brain was normal, magnetic resonance imaging (MRI) revealed an area of signal alteration on the diffusion-weighted image within the right protuberance. The second observation is a 15-year-old girl who developed sudden-onset ataxia. The CT scan and MRI of the brain revealed an acute bilateral cerebellar stroke. MRI angiography showed an anatomical variant of the left vertebral artery that did not participate in the Willis polygon. In these two observations, no other abnormalities were detected except they were homozygotous for MTHFR mutation in the first observation and minor alpha-thalassemia for the second one. The outcome in these two children was good without sequelae after a 6-month follow-up. The third observation is a 6-year-old girl who suddenly exhibited cephalalgia, ataxia, and left visual impairment. The brain MRI revealed left occipital and cerebellar strokes due to vertebral artery dissection. The authors recommend the systematic search for vertebral artery dissection in cases of infratentorial stroke.

Maturation of response time and attentional control in ADHD: evidence from an attentional capture paradigm.

Inattention and hyperactivity/impulsivity are the core symptoms of Attention Deficit/Hyperactivity Disorder (ADHD). Slowness, although less known, has been also recently reported in children with ADHD and may contribute to their learning difficulties. Slow response time and greater response time variability have been highlighted by several computerized tasks. The goal of the present work was to evaluate the age-related response time in ADHD children and in a group of matched control children during an attentional capture paradigm. The study population included 75 children with ADHD (aged between 6 and 13) and 75 age- and gender-matched typical developing children (Control group). The children with ADHD made more errors than children on the control group. The response times and the response time variability decreased with age in both groups and were significantly greater in ADHD than in controls. The distractor effect was similar in both groups. The maturation of response times and response time variability with age is quite similar in children with ADHD and typical developing children but whatever the age-class, children with ADHD were slower and exhibited greater response time variability than control children that could explain the variation during day-time of attention capacities in ADHD.

Microclimate influence on mineral and metabolic profiles of grape berries.

The grape berry microclimate is known to influence berry quality. The effects of the light exposure of grape berry clusters on the composition of berry tissues were studied on the "Merlot" variety grown in a vineyard in Bordeaux, France. The light exposure of the fruiting zone was modified using different intensities of leaf removal, cluster position relative to azimuth, and berry position in the cluster. Light exposures were identified and classified by in situ measurements of berry temperatures. Berries were sampled at maturity (>19 Brix) for determination of skin and/or pulp chemical and metabolic profiles based on (1) chemical and physicochemical measurement of minerals (N, P, K, Ca, Mg), (2) untargeted 1H NMR metabolic fingerprints, and HPLC targeted analyses of (3) amino acids and (4) phenolics. Each profile defined by partial least-square discriminant analysis allowed us to discriminate berries from different light exposure. Discriminant compounds between shaded and light-exposed berries were quercetin-3-glucoside, kaempferol-3-glucoside, myricetin-3-glucoside, and isorhamnetin-3-glucoside for the phenolics, histidine, valine, GABA, alanine, and arginine for the amino acids, and malate for the organic acids. Capacities of the different profiling techniques to discriminate berries were compared. Although the proportion of explained variance from the 1H NMR fingerprint was lower compared to that of chemical measurements, NMR spectroscopy allowed us to identify lit and shaded berries. Light exposure of berries increased the skin and pulp flavonols, histidine and valine contents, and reduced the organic acids, GABA, and alanine contents. All the targeted and nontargeted analytical data sets used made it possible to discriminate sun-exposed and shaded berries. The skin phenolics pattern was the most discriminating and allowed us to sort sun from shade berries. These metabolite classes can be used to qualify berries collected in an undetermined environment. The physiological significance of light and temperature effects on berry composition is discussed.

Candidate genes and QTLs for sugar and organic acid content in peach [ Prunus persica (L.) Batsch].

The identification of genes involved in variation of peach fruit quality would assist breeders in creating new cultivars with improved fruit quality. Major genes and quantitative trait loci (QTLs) for physical and chemical components of fruit quality have already been detected, based on the peach [ Prunus persica (L.) Batsch] cv. Ferjalou Jalousia((R)) (low-acid peach) x cv. Fantasia (normally-acid nectarine) F(2) intraspecific cross. Our aim was to associate these QTLs to structural genes using a candidate gene/QTL approach. Eighteen cDNAs encoding key proteins in soluble sugar and organic acid metabolic pathways as well as in cell expansion were isolated from peach fruit. A single-strand conformation polymorphism strategy based on specific cDNA-based primers was used to map the corresponding genes. Since no polymorphism could be detected in the Ferjalou Jalousia((R)) x Fantasia population, gene mapping was performed on the almond [ Prunus amygdalus ( P. dulcis)] cv. Texas x peach cv. Earlygold F(2) interspecific cross from which a saturated map was available. Twelve candidate genes were assigned to four linkage groups of the peach genome. In a second step, the previous QTL detection was enhanced by integrating anchor loci between the Ferjalou Jalousia((R)) x Fantasia and Texas x Earlygold maps and data from a third year of trait assessment on the Ferjalou Jalousia((R)) x Fantasia population. Comparative mapping allowed us to detect a candidate gene/QTL co-location. It involved a cDNA encoding a vacuolar H(+)-pyrophosphatase ( PRUpe;Vp2) that energises solute accumulation, and QTLs for sucrose and soluble solid content. This preliminary result may be the first step in the future development of marker-assisted selection for peach fruit sucrose and soluble solid content.

Modeling Carbon Export Out of Mature Peach Leaves.

The characteristics of sorbitol and sucrose export out of mature leaves in seedlings of peach (Prunus persica L. Batsch cv GF 305) were investigated by simulating carbon fluxes through the leaf. Three treatments were employed: a control treatment and two treatments modifying leaf export, the latter using either shading or girdling. Photosynthesis and 14C partitioning into sorbitol and sucrose were measured during carbohydrate pool buildup at the beginning of the photoperiod, and the export rate of sorbitol and sucrose was modeled using a PSPICE (Simulation Program with Integrated Circuit Emphasis) simulator. The simulation allowed prediction of the resulting sorbitol and sucrose contents, which were compared to experimental carbohydrate contents. The apparent Km for sorbitol and sucrose phloem loading, estimated by carbon flux modeling, was 6.6 and 4 mol m-3, respectively. The predicted export capacity of the leaf, characterized by the estimated Vmax values for phloem loading of sorbitol and sucrose, was similar to the photosynthetic carbon flux measured under the leaf growth conditions. This export capacity was enhanced in plants in which all leaves except those studied were shaded. The mature leaf had a higher storage capacity for sorbitol than for sucrose in control plants, especially in the girdled treatment. Sucrose content appears to be tightly regulated.

Carbon fluxes in mature peach leaves.

The turnover and transport of sugars are described in peach (Prunus persica L. Batsch), a species exporting both sucrose and sorbitol. Apparent export rate was slower in peach leaves than in leaves of herbaceous species. Sorbitol was the major soluble end product of photosynthesis and the major soluble carbohydrate in the leaf (higher than sucrose). Carbon fluxes were described using (14)C labeling, radioactivity loss curves, and compartmental analysis during the second half of the photoperiod when chemical steady state was reached for soluble carbohydrates. The measured specific radioactivity of sucrose was typical of a primary product. The delayed decrease in specific radioactivity of sorbitol indicated that part of it was secondarily synthesized. Sucrose is proposed to be the carbon source for the delayed synthesis of sorbitol in the light. The sorbitol to sucrose ratio was higher in the petiole than in the leaf tissues. In phloem sap, obtained using stylectomy of aphids and collected from the main stem between source leaves and apex, this ratio was lower than in the petiole, suggesting a preferential sorbitol demand by sinks.

Carbon and nitrogen partitioning in peach/plum grafts.

Modifications in root-shoot relationships induced by graft incompatibility were studied in peach/plum graft combinations by means of carbohydrate and nitrogen analyses and isotope labeling. Mobilization of stored carbon, phloem transport of carbon, and mobilization, assimilation and distribution of nitrogen were studied in one compatible peach/plum graft (Prunus persica L. Batsch cv. springtime grafted on Prunus cerasifera L. Ehrh cv. myrobalan P 2032) and one incompatible graft (Prunus persica L. Batsch cv. Springtime grafted on Prunus cerasifera L. Ehrh cv. myrobalan P 18) for 89 days after grafting. Carbon and nitrogen reserves were mobilized in the rootstock in both graft combinations during the first 78 days following grafting. After that, sorbitol concentration was lower in the roots of the incompatible graft than in the roots of the compatible graft, whereas soluble sugars and starch accumulated in the peach scion of the incompatible graft. In both graft types, carbon was allocated mainly to the scion. Labeling with (13)CO(2) from 78 to 81 days after grafting showed that carbon partitioning among the different plant organs was only slightly affected by graft incompatibility. Carbohydrate concentrations provided indirect evidence that carbon transfer to the roots was hindered in the incompatible graft. Labeling with (15)NO(3) showed that nitrogen distribution and the rate of nitrogen assimilation were similar in the two graft combinations from 57 to 78 days after grafting. Nitrogen assimilation in the incompatible graft ceased 78 days after grafting, whereas it continued in the compatible graft.

Growth, cambial activity and phloem structure in compatible and incompatible peach/plum grafts.

Peach (Prunus persica L. Batsch) shoots grafted onto compatible or incompatible clones of rootstocks of myrobolan plum (Prunus cerasifera L. Ehrh. cv. myrobolan) were observed in a greenhouse for 100 days after grafting. The incompatible grafts showed foliar symptoms of incompatibility and reduced shoot growth about 60 days after grafting. Light microscopic studies revealed that cambial activity stopped earlier in the rootstocks, than in the scions, of incompatible grafts. Structural modifications were also observed in the phloem of incompatible grafts. Compared with the compatible graft rootstock, the number of sieve elements differentiated from the cambial zone was reduced in the incompatible graft rootstock, whereas the production of parenchyma cells was not affected. No important ultrastructural alteration was observed in the sieve tubes of the incompatible grafts. However, osmiophilic granulations near the plasma membrane of sieve plates were observed more frequently in the rootstocks of incompatible grafts than in ungrafted myrobolan controls. It is concluded that the external symptoms of incompatibility are not related to massive structural modifications or degeneration of the conducting tissues.

Growth and the composition and transport of carbohydrate in compatible and incompatible peach/plum grafts.

The growth of scions and rootstocks of compatible (Prunus persica L. Batsch cv. Springtime/Prunus cerasifera L. Ehrh. cv. myrobolan P2032) and incompatible (Prunus persica L. Batsch cv. Springtime/Prunus cerasifera L. Ehrh. cv. myrobolan P18) peach/plum grafts were compared. The composition of soluble carbohydrates in phloem and cortical tissues of both peach/plum grafts and ungrafted plums and the translocation of these compounds across the union of grafted plants were examined. Sorbitol and sucrose were the dominant sugars in the phloem and cortical tissues of plum. A cyanogenic glycoside, prunasin, was present in peach tissues in amounts equivalent to those of sorbitol or sucrose, whereas only small amounts of prunasin were detected in plum tissues. The concentration of prunasin was significantly higher in the phloem of the P18 rootstock of the incompatible graft. Sorbitol was the only sugar significantly depleted in rootstock tissues of the incompatible graft when the first foliar symptoms of graft incompatibility became evident. Translocation studies with 1-(14)C-deoxyglucose showed that the relative distribution of radioactivity across the graft union was similar in both compatible and incompatible grafts. However, the total amount of radioactivity translocated across the incompatible graft was less than one-third of that translocated across the compatible graft. The results are consistent with the hypothesis of a progressive poisoning of the root system in the incompatible graft by a compound synthesized in peach foliage. The role of prunasin as a possible candidate is discussed.