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Resume Face a une forte augmentation de la prevalence du diabete gestationnel (DG) et des demandes de prise en charge, une demarche d’optimisation de celle-ci a ete mise en œuvre au sein de notre service hospitalier de diabetologie. Elle repose sur la mise en place de trois composants indissociables et complementaires : un programme d’education therapeutique ambulatoire des patientes, une proposition de telesurveillance, et un protocole de cooperation entre professionnels de sante. Cette demarche, mise en place en 2014, semble une solution tres interessante, plebiscitee a la fois par les patientes et les professionnels de sante correspondants, et au sein de l’equipe elle-meme, dont temoigne la progression reguliere du nombre de patientes adressees.

Dental caries is a multifactorial condition that remains a major public health issue in high income countries. The prevalence of dental caries in children has markedly declined in most countries over the past 30 years. However, the disease continues to affect a vulnerable population defined as a high-risk group. As many public health policies are inefficient in dealing with this underprivileged group, it is necessary to find other strategies to decrease the incidence and the burden of dental caries. Defining dental caries as a chronic disease enables us to develop the concept of 'therapeutic patient education.' It is meant to train patients to self-manage or adapt treatment to their particular chronic disease and to cope with new processes and skills. The purpose of this paper is to propose a new approach to dental caries, in particular to early childhood caries. That should decrease the gravity and prevalence of the disease in this specific population. As a result, this new approach could increase the quality of life of many children both in terms of function and aesthetics.

Summary Introduction Giant ameloblastomas are more common in developing countries. They raise a serious problem of management. We present the case of one of the largest ameloblastoma ever reported. Case report A 48-year-old Congolese female patient was referred for mandibular swelling having begun 23 years before and now inducing severe functional disorders. A cephalic CT scan revealed a multicystic mass, 30 × 18 × 10 cm in size, with a typical “soap bubble” presentation, and with thinned and inflated cortical bone. The treatment was sub-total segmental mandibulectomy with immediate reconstruction using a fibular free flap, modeled on the sampling site by four ostectomies. The pathological examination confirmed the diagnosis of a benign follicular and plexiform ameloblastoma. The excess of soft tissue was treated with a right commissuroplasty on the 15th postoperative day. There was no complication. Discussion Radical treatment followed by immediate reconstruction using a free flap is the treatment of choice for giant mandibular ameloblastomas, when considering immediate functional and esthetic benefits. This is a prime concern for patients with a difficult access to health care and for whom long-term follow-up is not feasible.

Symposium on Advances in Agrochemicals: Ion Channels and G Protein-Coupled Receptors (GPCRs) as Targets for Pest Control / 252nd ACS National Meeting and Exposition, 21-25 aôut 2016 Philadelphia, PA – États-Unis.; International audience; Voltage-gated Ca2+ (CaV) channels allow Ca2+ to enter the cell in response to membrane depolarization. This Ca2+ influx is not only necessary for cell excitability, but also triggers, via Ca2+-binding proteins, important biological functions such as contraction, synaptic transmission, or gene expression. Insect CaV channels are encoded by only three genes (against 10 in mammals), and their invalidation or pharmacological blockade is expected to have deleterious effects. They may thus constitute interesting targets for specific insecticides. However, the precise identification of the genes underlying the different Ca2+ currents recorded in different tissues, as well as the heterologous expression of these genes to screen selective molecules, have been proven to be difficult. This chapter reports on the recent successful expression of honeybee Ca2+ channels genes in Xenopus oocytes and reviews pharmacological properties of Ca2+ currents recorded in isolated honeybee neurons and muscle cells.

Key message We propose a statistical criterion to optimize multi-environment trials to predict genotype × environment interactions more efficiently, by combining crop growth models and genomic selection models. Abstract Genotype × environment interactions (GEI) are common in plant multi-environment trials (METs). In this context, models developed for genomic selection (GS) that refers to the use of genome-wide information for predicting breeding values of selection candidates need to be adapted. One promising way to increase prediction accuracy in various environments is to combine ecophysiological and genetic modelling thanks to crop growth models (CGM) incorporating genetic parameters. The efficiency of this approach relies on the quality of the parameter estimates, which depends on the environments composing this MET used for calibration. The objective of this study was to determine a method to optimize the set of environments composing the MET for estimating genetic parameters in this context. A criterion called OptiMET was defined to this aim, and was evaluated on simulated and real data, with the example of wheat phenology. The MET defined with OptiMET allowed estimating the genetic parameters with lower error, leading to higher QTL detection power and higher prediction accuracies. MET defined with OptiMET was on average more efficient than random MET composed of twice as many environments, in terms of quality of the parameter estimates. OptiMET is thus a valuable tool to determine optimal experimental conditions to best exploit MET and the phenotyping tools that are currently developed. Electronic supplementary material The online version of this article (doi:10.1007/s00122-017-2922-4) contains supplementary material, which is available to authorized users.

International audience; Genetic (Pinb-D1 alleles) and environment (through vitreousness) have important effects on bread wheat milling behavior. SKCS optimal values corresponding to soft vitreous or hard mealy grains were defined to obtain the highest total flour yield.Near-isogenic lines of bread wheat that differ in hardness, due to distinct puroindoline-b alleles (the wild type, Pinb-D1a, or the mutated forms, Pinb-D1b or Pinb-D1d), were grown in different environments and under two nitrogen fertilization levels, to study genetic and environmental effects on milling behavior. Milling tests used a prototype mill, equipped with two break steps, one sizing step, and two reduction steps, and this enabled 21 individual or aggregated milling fractions to be collected. Four current grain characters, thousand grain weight, test weight, grain diameter, and protein content, were measured, and three characters known to influence grain mechanical resistance, NIRS hardness, SKCS hardness index, and grain vitreousness (a character affecting the grain mechanical behavior but generally not studied). As expected, the wild type or mutated forms of Pinb-D1 alleles led to contrasted milling behavior: soft genotypes produced high quantities of break flour and low quantities of reduction flour, whereas reverse quantities were observed for hard genotypes. This different milling behavior had only a moderate influence on total flour production. NIRS hardness and vitreousness were, respectively, the most important and the second most important grain characters to explain milling behavior. However, contrary to NIRS hardness, vitreousness was only involved in endosperm reduction and not in the separation between the starchy endosperm and the outer layers. The highest flour yields were obtained for SKCS values comprised between 30 and 50, which corresponded either to soft vitreous or hard mealy grains. Prediction equations were defined and showed a good accuracy estimating break and reduction flours portions, but should be used more cautiously for total flour.

Voltage‐gated Ca2+ channels are key transducers of cellular excitability and participate in several crucial physiological responses. In vertebrates, 10 Ca2+ channel genes, grouped in 3 families (CaV1, CaV2 and CaV3), have been described and characterized. Insects possess only one member of each family. These genes have been isolated in a limited number of species and very few have been characterized although, in addition to their crucial role, they may represent a collateral target for neurotoxic insecticides. We have isolated the 3 genes coding for the 3 Ca2+ channels expressed in Apis mellifera. This work provides the first detailed characterization of the honeybee T-type CaV3 Ca2+ channel and demonstrates the low toxicity of inhibiting this channel. Comparing Ca2+ currents recorded in bee neurons and myocytes with Ca2+ currents recorded in Xenopus oocytes expressing the honeybee CaV3 gene suggests native expression in bee muscle cells only. High‐voltage activated Ca2+ channels could be recorded in the somata of different cultured bee neurons. These functional data were confirmed by in situ hybridization, immunolocalization and in vivo analysis of the effects of a CaV3 inhibitor. The biophysical and pharmacological characterization and the tissue distribution of CaV3 suggest a role in honeybee muscle function.

Heparin is a widely used intravenous anticoagulant comprising of a very complex mixture of glycosaminoglycan chains, mainly derived from porcine intestinal mucosa. The species of origin and the absence of contaminants from other species are important determinants of the different physicochemical characteristics of heparin. They also determine the potential for introducing infectious and adventitious agents into heparin batches destined for medicinal use. We perform routine quantitative polymerase chain reaction (Q-PCR) release tests to confirm the quality of all crude heparin batches, including those used for the manufacture of enoxaparin sodium. Here we further demonstrate that the assessment of the DNA content in crude heparin is a good surrogate marker of contamination at the mucosa level. After spiking porcine mucosa with ovine mucosa and processing this material to form crude heparin, we were able to observe similar ratios of species-specific DNA in both the starting and end products. Experiments performed with 3,000 and 1,500 ppm contamination found these concentrations to be well above the detection limit for our assay of heparin batches. Additionally this Q-PCR method can be used to detect contamination in mucosa, thus providing a tool capable of monitoring for contaminants throughout the crude heparin manufacturing process. Q-PCR analysis of industrial crude heparin samples has confirmed over time the value of this method to assess the pure porcine origin of heparin.

Resume Introduction Si, malgre les recommandations du Programme national nutrition sante (PNNS), la consommation de fruits et legumes demeure insuffisante, une hausse des ventes de jus de fruits, et par extension des boissons aux fruits, commercialises comme des produits « bons pour la sante », est observee. Objectif L’objectif de cette etude etait de mettre en evidence la teneur en sucres des jus de fruits, des boissons a base de jus de fruits et des eaux aromatisees aux fruits. Materiel et methodes Un echantillon de jus de fruits, nectars, boissons aux fruits et eaux aromatisees a ete selectionne dans la grande distribution. Les variables etudiees etaient les teneurs en sucres (g/100 mL), en jus de fruits (%) et la presence de sucres ajoutes. Resultats Cent quatre-vingt-sept boissons ont ete etudiees. La teneur moyenne en sucres variait de 2,4 g/100 mL a 10,8 g/100 mL selon les groupes. Les sucres ajoutes etaient presents dans les nectars, les boissons aux fruits et dans 71,4 % des eaux aromatisees. Conclusion Les jus de fruits, boissons aux fruits et eaux aromatisees sont riches en sucres. Une meilleure information des familles est indispensable pour en limiter la consommation repetee ; celle ci constitue, en effet, un facteur de risque commun a l’obesite et a la carie dentaire, deux pathologies qui impactent la qualite de vie. La cooperation entre les medecins, les dieteticiens et les chirurgiens-dentistes permettrait de developper une approche commune du risque pour lutter de facon efficace contre le surpoids et la carie dentaire.

Resume Les luxations sternoclaviculaires sont rares et souvent meconnues initialement. Le diagnostic est donc souvent fait secondairement lors de l’apparition de symptomes secondaires a la compression des structures vasculoaeriennes. Une douleur intense, malgre une imagerie radiologique standard peu contributive, doit attirer l’attention, les deformations locales etant rapidement masquees par l’œdeme et l’hematome. Elles peuvent entrainer de graves complications chez les sujets jeunes qu’elles touchent plus particulierement, notamment dans des traumatismes a haute energie lors d’accidents motorises et de sports. Toute tentative de reduction chirurgicale ou orthopedique doit etre faite au bloc operatoire. De plus, devant une telle luxation instable ou irreductible, une reduction a ciel ouvert, completee par une stabilisation chirurgicale, est indiquee.

UMR IATE Axe 1 : Fractionnement des Agro ressources : bases structurales et physicochimiques ; procédés de broyage, extraction et de séparation; Genetic (different forms of puroindoline-b) and environment (through variations in vitreousness), have important effects on wheat grain mechanical properties. The two methods of hardness measurements (NIRS, SKCS) do not give the same information. Bread wheat near-isogenic lines differing in hardness, due to distinct puroindoline-b alleles (the wild type, Pinb-D1a, or the mutated forms, Pinb-D1b or Pinb-D1d), were grown for three years in seven sites and under two nitrogen fertilization levels, to study genetic and environmental effects on grain mechanical properties. Two methods, Near-Infrared Reflectance Spectroscopy (NIRS) and Single Kernel Characterization System (SKCS), currently used for grain hardness characterization, were carried out. Grain vitreousness, which is known to affect the grain mechanical behavior but is generally not studied, was also measured, as well as three other characters (Thousand Grain Weight, Test Weight and protein content). The relationships between the different characters were studied. Results revealed a clear effect of the different Pinb-D1 alleles on NIRS hardness, and a marked impact of the environmental conditions on vitreousness. SKCS hardness was influenced by both Pinb-D1 alleles and environmental conditions. The relationship between SKCS and NIRS hardness was strong when considering together soft and hard genotypes, but moderate within a class of genetical hardness. Vitreousness had only a weak effect on NIRS hardness, whereas vitreousness and SKCS values were strongly correlated, with two distinct regressions for soft and hard genotypes. Vitreousness was positively related to protein content, especially in the case of hard genotypes, which were able to reach high vitreousness values never observed for soft genotypes

The β subunits of voltage-gated Ca 2+ channels are known to be regulators of the channels' gating properties. Here we report a striking additional function of a β subunit. Screening of chicken cochlear and brain cDNA libraries identified β 4c , a short splice variant of the β 4 subunit. Although β 4c occurs together with the longer isoforms β 4a or β 4b in the brain, eye, heart, and lung, the cochlea expresses exclusively β 4c . The association of β 4c with the Ca 2+ -channel α 1 subunit has slight but significant effects on the kinetics of channel activation and inactivation. Yeast two-hybrid and biochemical assays revealed that β 4c interacts directly with the chromo shadow domain of chromobox protein 2/heterochromatin protein 1γ (CHCB2/HP1γ), a nuclear protein involved in gene silencing and transcriptional regulation. Coexpression of this protein specifically recruits β 4c to the nuclei of mammalian cells. Furthermore, β 4c but not β 4a dramatically attenuates the gene-silencing activity of chromobox protein 2/heterochromatin protein 1γ. The β 4c subunit is therefore a multifunctional protein that not only constitutes a portion of the Ca 2+ channel but also regulates gene transcription.

We have identified previously a repressor element in the transcription start site region of the cyclin E1 promoter that periodically associates with an atypical, high molecular weight E2F complex, termed CERC. Purification of native CERC reveals the presence of the type II arginine methyltransferase PRMT5, which can mono- or symetrically dimethylate arginine residues in proteins. Chromatin immunoprecipitations (ChIPs) show that PRMT5 is associated specifically with the transcription start site region of the cyclin El promoter. ChIP analyses also show that this correlates with the presence on the same promoter region of arginine-methylated proteins including histone H4, an in vitro substrate of PRMT5. Consistent with its presence within the repressor complex, forced expression of PRMT5 negatively affects cyclin E1 promoter activity and cellular proliferation, effects that require its methyltransferase activity. These data provide the first direct experimental evidence that a type II arginine methylase is involved in the control of transcription and proliferation.

Stargazin or γ2, a protein selectively expressed in the brain with homology to the skeletal muscle L-type Ca2+ channel γ1 subunit (Bosse et al. 1990; Pragnell et al. 1991) was recently discovered as the product of the gene mutated by insertion of a retrotransposon in the stargazer mouse model of petit mal epilepsy and ataxia (Letts et al. 1998). In skeletal muscle, γ1 can be co-immunoprecipitated from muscle extracts with the pore-forming L-type Ca2+ channel subunit α1S (Flockerzi et al. 1986a, b; Sieber et al. 1987). The γ1 subunit is a 32 kDa, 222 amino acid, glycosylated transmembrane protein with 10 cysteines that are supposed to form disulfide bridges of major importance for the secondary structure of the native protein (Bosse et al. 1990; Pragnell et al. 1991). Co-expression of γ1 with L-type (α1C or CaV1.2) or P/Q-type (α1A or CaV2.1) Ca2+ channels in heterologous systems has evidenced minor modulatory function including slight changes in the activation and inactivation properties and modification in the peak current amplitude of these Ca2+ channels (Mori et al. 1991; Wei et al. 1991; Singer Lahat et al. 1994; Sipos et al. 1995; Eberst et al. 1997; Ren & Hall, 1997; Freise et al. 2000). The stargazin protein displays 38 % similarity (25 % identity) with γ1 and shares the same gene organization and protein secondary structure including four putative transmembrane segments (Letts et al. 1998; Klugbauer et al. 2000). The stargazer mouse has recessively inherited epilepsy and ataxia characterized by spike wave seizures, characteristic of petit mal or absence epilepsy (Chen et al. 1999). Cerebellar disorders have also been noted, including, most prominently, abnormal migration and maturation and reduced brain-derived neurotrophic factor production of cerebellar granule cells. These features are coincindent with the start of ataxia (Qiao et al. 1996, 1998). Immature or reduced synaptic transmission at parallel fibre-Purkinje cell synapses, Golgi cell-granule cell synapses and mossy fibre-granule cell synapses has also been noticed (Chen et al. 1999; Hashimoto et al. 1999), suggesting a crucial role of the γ2/stargazin protein for normal synaptic transmission. The phenotypic similarities between stargazer mice and the other neurological mutant mice, tottering and lethargic, which have defects in genes encoding the α1A and β4 subunits of the P/Q-type Ca2+ channels, together with the homology of gene and protein structures with the γ1 subunit, have led to the hypothesis that the γ2 subunit is indeed a Ca2+ channel subunit and suggest a channel dysfunction as the basis of the disease. Three new members of this family (γ3, γ4 and γ5) have now been isolated in mice and humans (Black & Lennon, 1999; Klugbauer et al. 2000). Co-expression studies of these four γ subunits with the L-type (α1C) or P/Q-type (α1A) Ca2+ channels did not change the kinetics and voltage dependence of activation of the channel (Klugbauer et al. 2000). Analysis of the effects of these γ subunits on channel inactivation has produced contradictory results, and shifts in the steady-state inactivation curves in both the depolarized and the hyperpolarized direction have been reported, depending on the α1 and β subunits (α1A, α1C, β1 or β2) used, as well as the cation used as charge carrier (Ba2+versus Ca2+, Klugbauer et al. 2000). These data suggest that the subunit composition of the channel might be an important determinant of the effects of the γ subunits on channels properties, and therefore on the physiopathological consequences of its absence in the stargazer mice. In this work we have analysed the effects of human γ2, γ3 and γ4 subunits and the modulatory roles of the β1, β2, β3 and β4 subunits on P/Q-type Ca2+ channel properties.

Three populations of 41 to 74 homozygous recombinant substitutionlines (RSLs) were used for RFLP mapping and quantitative trait analysis ofthe following parameters: total proteins (%prot), SDS-sedimentationvolume (SDSsed), bread mixing time (Bmxt) and loaf volume (Blvol). TheRSLs were developed from crosses between disomic substitution linesinvolving chromosomes 1A, 1B, and 1D of the high-quality wheat cv.`Cheyenne' (Cnn) substituted into the genetic background of the poorquality cv. `Chinese Spring' (CS). The QTL analysis indicated regions in thethree chromosomes responsible for the differences between CS and thethree disomic substitution lines. The major effect detected on chromosome1A of Cnn was high SDSsed, Bmxt and Blvol associated with the H-M-WGlutenin subunit locus Glu-A1. In addition a QTL was identifieddistally on the long arm of chromosome 1A for Bmxt and Blvol. Ahigh %prot QTL was mapped on the long arm of chromosome 1B of CSand a high Bmxt QTL was mapped on the long arm of chromosome 1B ofCnn. Additionally, this chromosome enhanced SDSsed, Bmxt and Blvol,which were associated with the region of the gliadin and L-M-W Gluteninsubunit locus Gli-B1/Glu-B3. A second more proximal region on theshort arm of chromosome 1B could be involved in loaf volume. QTLanalyses for% prot, showed a strong clear QTL mapped in the centromericregion (XTri/Centromere linkage group) of chromosome 1D with anapparent positive effect brought by CS. For Blvol we revealed two QTLs inopposite phase: one in the Xtri/Centromere region with a positive effect ofCS allele, one in the Glu-D1 region with a positive effect of Cnnallele. This organization `in repulsion' in the parental lines could explain thesmall difference between them for Blvol and the significant transgressionobserved among the RSLs. No clear candidate gene explained the positiveeffect of the centromeric region of CS on %prot and Blvol. Contrary to thecurrent belief that wheat bread-making quality is determined primarily byvariation at the Glu-1 locus, present results showed that the trait isunder a complex control and the Glu-1 loci was only a component ofthe genetic control of the trait.

Small RGK GTPases, Rad, Gem, Rem1, and Rem2, are potent inhibitors of high-voltage-activated (HVA) Ca(2+) channels expressed in heterologous expression systems. However, the role of this regulation has never been clearly demonstrated in the nervous system. Using transcriptional analysis, we show that peripheral nerve injury specifically upregulates Gem in mice dorsal root ganglia. Following nerve injury, protein expression was increased in ganglia and peripheral nerve, mostly under its phosphorylated form. This was confirmed in situ and in vitro in dorsal root ganglia sensory neurons. Knockdown of endogenous Gem, using specific small-interfering RNA (siRNA), increased the HVA Ca(2+) current only in the large-somatic-sized neurons. Combining pharmacological analysis of the HVA Ca(2+) currents together with Gem siRNA-transfection of larger sensory neurons, we demonstrate that only the P/Q-type Ca(2+) channels were enhanced. In vitro analysis of Gem affinity to various CaVβx-CaV2.x complexes and immunocytochemical studies of Gem and CaVβ expression in sensory neurons suggest that the specific inhibition of the P/Q channels relies on both the regionalized upregulation of Gem and the higher sensitivity of the endogenous CaV2.1-CaVβ4 pair in a subset of sensory neurons including the proprioceptors. Finally, pharmacological inhibition of P/Q-type Ca(2+) current reduces neurite branching of regenerating axotomized neurons. Taken together, the present results indicate that a Gem-dependent P/Q-type Ca(2+) current inhibition may contribute to general homeostatic mechanisms following a peripheral nerve injury.

Giant ameloblastomas are more common in developing countries. They raise a serious problem of management. We present the case of one of the largest ameloblastoma ever reported.A 48-year-old Congolese female patient was referred for mandibular swelling having begun 23 years before and now inducing severe functional disorders. A cephalic CT scan revealed a multicystic mass, 30×18×10cm in size, with a typical "soap bubble" presentation, and with thinned and inflated cortical bone. The treatment was sub-total segmental mandibulectomy with immediate reconstruction using a fibular free flap, modeled on the sampling site by four ostectomies. The pathological examination confirmed the diagnosis of a benign follicular and plexiform ameloblastoma. The excess of soft tissue was treated with a right commissuroplasty on the 15th postoperative day. There was no complication.Radical treatment followed by immediate reconstruction using a free flap is the treatment of choice for giant mandibular ameloblastomas, when considering immediate functional and esthetic benefits. This is a prime concern for patients with a difficult access to health care and for whom long-term follow-up is not feasible.

Amelogenesis imperfecta (AI) represents a group of hereditary conditions which affects enamel formation in the primary and permanent dentitions. Gene mutations alter the quality and/or quantity of enamel. AI often has severe consequences for the patient such as high tooth sensitivity, low aesthetic quality of the dentition, and poor mechanical properties of the dental tissues. This can result in reduced oral health-related quality of life. We present the case of a child affected by AI which had been diagnosed at the age of 9 years. Teeth presented many enamel defects. The patient presented thin brown to yellow enamel and the surface was rough and granular. He revealed short clinical crowns, occlusal wear with exposed dentine in posterior areas. He also presented a lateral open bite and lingual lateral interposition due to partial destruction of deciduous molars. Panoramic radiograph showed no differences between enamel and dentine appearance and also coronary destruction of permanent molars. The initial treatment consisted of adaptation of composite resins on permanent incisors to improve aesthetics. Preformed metal crowns were placed on first permanent molars to prevent their premature destruction. This was disrupted for a variety of reasons. Fourteen years later, after a dental nomadism, the patient consulted by chance a dentist who identified his genetic pathology and was aware of its consequences. Extensive prosthodontic treatment was needed, but oral hygiene was poor and gingivitis remained. Dealing with high loss of motivation has been one of the main challenges because this patient had a lot of psychological problems. He was concerned, as are many patients affected by AI or other enamel abnormalities. This paper highlights the difficulties of long-term care of this dental abnormality. Psychological aspects of the quality of life, which is a common feature in patients suffering from many kinds of enamel anomalies, are very important.

International audience; In France, a stagnation of bread wheat yield has been observed since the middle of the 1990s, and the possibility of a decline in breeding progress has been questionned. To investigate this hypothesis, we have considered 2 independent long time series of yield data: one corresponding to the registration trials conducted in France from 1976 to 2010, and the other corresponding to trials from the INRA bread wheat breeding program along the 1970-2010 period. These raw data related to potential bread wheat yield in France, exhibited the same trend to stagnation as observed on national yield in the farms. However, after correction of the "year" effects, the corrected yields appeared to have increased regularly from the 1970s up to now, with quite a high rate in intensive conditions (from 0.065 t ha(-1) yr(-1) to 0.137 t ha(-1) yr(-1)). This linear trend for genetic progress was even higher without fungicide (from 0.097 t ha(-1) yr(-1) to 0.158 t ha(-1) yr(-1)), which could indicate that breeding efforts for productivity and for resistance to diseases tended to have additive results. The corrected yields also enabled us to point out a marked degradation of the agro-climatic potential of the different years. As our registration and breeding trials were as free as possible from agronomic limiting factors, it appeared that climatic factors constituted the main explanation to this degradation. Thus, our study demonstrated that since the end of the 1980s, genetic progress has been partly or totally counterbalanced by the adverse effects of climate change. (C) 2012 Elsevier B.V. All rights reserved.

The modification of flowering date is considered an important way to escape the current or future climatic constraints that affect wheat crops. A better understanding of its genetic bases would enable a more efficient and rapid modification through breeding. The objective of this study was to identify chromosomal regions associated with earliness in wheat. A 227-wheat core collection chosen to be highly contrasted for earliness was characterized for heading date. Experiments were conducted in controlled conditions and in the field for 3 years to break down earliness in the component traits: photoperiod sensitivity, vernalization requirement and narrow-sense earliness. Whole-genome association mapping was carried out using 760 molecular markers and taking into account the five ancestral group structure. We identified 62 markers individually associated to earliness components corresponding to 33 chromosomal regions. In addition, we identified 15 other significant markers and seven more regions by testing marker pair interactions. Co-localizations were observed with the Ppd-1, Vrn-1 and Rht-1 candidate genes. Using an independent set of lines to validate the model built for heading date, we were able to explain 34% of the variation using the structure and the significant markers. Results were compared with already published data using bi-parental populations giving an insight into the genetic architecture of flowering time in wheat.

Trente-trois hybrides de ble tendre d'hiver produits par voie chimique ont ete compares a leurs 27 parents pour la qualite. Les echantillons de grains utilises pour les tests technologiques provenaient d'une experimentation multilocale, mais les interactions genotypes x milieux sont apparues negligeables pour la durete, le Pelshenke et l'alveographe Chopin. Aucun heterosis par rapport au parent superieur n'a ete mis en evidence pour ces 3 tests, ni pour la teneur en proteines: la F1 se situe generalement entre ses 2 parents. Dans le cas de la teneur en proteines, ce resultat semble indiquer une relation source-puits plus favorable chez les hybrides que chez les parents, car le taux de proteines est maintenu chez la F1 alors qu'il existe un heterosis significatif pour le rendement en grains

The initiation of flowering is a crucial trait that allows temperate plants to flower in the favourable conditions of spring. The timing of flowering initiation is governed by two main mechanisms: vernalization that defines a plant's requirement for a prolonged exposure to cold temperatures; and photoperiod sensitivity defining the need for long days to initiate floral transition. Genetic variability in both vernalization and photoperiod sensitivity largely explains the adaptability of cultivated crop plants such as bread wheat (Triticum aestivum L.) to a wide range of climatic conditions. The major genes controlling wheat vernalization (VRN1, VRN2, and VRN3) and photoperiod sensitivity (PPD1) have been identified, and knowledge of their interactions at the molecular level is growing. However, the quantitative effects of temperature and photoperiod on these genes remain poorly understood. Here it is shown that the distinction between the temperature effects on organ appearance rate and on vernalization sensu stricto is crucial for understanding the quantitative effects of the environmental signal on wheat flowering. By submitting near isogenic lines of wheat differing in their allelic composition at the VRN1 locus to various temperature and photoperiod treatments, it is shown that, at the whole-plant level, the vernalization process has a positive response to temperature with complex interactions with photoperiod. In addition, the phenotypic variation associated with the presence of different spring homoeoalleles of VRN1 is not induced by a residual vernalization requirement. The results demonstrate that a precise definition of vernalization is necessary to understand and model temperature and photoperiod effects on wheat flowering. It is suggested that this definition should be used as the basis for gene expression studies and assessment of functioning of the wheat flowering gene network, including an explicit account of the quantitative effect of environmental variables.

International audience; Earliness is very important for the adaptation of wheat to environmental conditions and the achievement of high grain yield. A detailed knowledge of key genetic components of the life cycle would enable an easier control by the breeders. The objective of the study was to investigate the effect of candidate genes on flowering time. Using a collection of hexaploid wheat composed of 235 lines from diverse geographical origins, we conducted an association study for six candidate genes for flowering time and its components (vernalization sensitivity and earliness per se). The effect on the variation of earliness components of polymorphisms within the copies of each gene was tested in ANOVA models accounting for the underlying genetic structure. The collection was structured in five groups that minimized the residual covariance. Vernalization requirement and lateness tend to increase according to the mean latitude of each group. Heading date for an autumnal sowing was mainly determined by the earliness per se. Except for the Constans (CO) gene orthologous of the barley HvCO3, all gene polymorphisms had a significant impact on earliness components. The three traits used to quantify vernalization requirement were primarily associated with polymorphisms at Vrn-1 and then at Vrn-3 and Luminidependens (LD) genes. We found a good correspondence between spring/winter types and genotypes at the three homeologous copies of Vrn-1. Earliness per se was mainly explained by polymorphisms at Vrn-3 and to a lesser extent at Vrn-1, Hd-1 and Gigantea (GI) genes. Vernalization requirement and earliness as a function of geographical origin, as well as the possible role of the breeding practices in the geographical distribution of the alleles and the hypothetical adaptive value of the candidate genes, are discussed.

A 2.3-kb plasmid present in about 20 copies per genome was identified in extracts of Desulfovibrio desulfuricans G100A and designated pBG1. It appears to be unable to replicate in Escherichia coli. Although composite plasmids of pBG1 inserted into pTZ18U are stable in E. coli, few if any pBG1-specific transcripts are detectable. The plasmid sequence reveals several features typical of the origin of replication of non-ColE1 enterobacterial plasmids as well as several potential open reading frames. This small replicon has been shown to support the replication of recombinant plasmids in D. desulfuricans G100A and Desulfovibrio fructosovorans. A conjugable shuttle vector has been constructed.

Attempts have been made to predict Chopin alveograph or French bread-making tests, using tree-based models and PLS regressions. Data came from three sets of trials, involving 130, 214 and 103 different genotypes, which were described for HMW-GS, LMW-GS and small-scale tests currently used in breeding programs. Segmentation trees and PLS regressions indicated that HMW-GS and LMW-GS were not sufficient to explain alone the variability of bread wheat quality. This could be partly due to “allele × environment” and “locus × locus” interactions. For HMW-GS, Glu-B1 was the predominant locus for alveograph and French bread-baking, and some differences in the alleles hierarchy were demonstrated according to the end-use parameter considered. For LMW-GS, Glu-B3 seemed to be preponderant, with alleles b′, c and g being favourable and allele c′ unfavourable. Joint use of the information brought by glutenin subunits and technological tests did not enable to predict satisfactorily, neither the different parameters of French bread-baking, nor the extensibility L of alveograph. Only the prediction of the strength W proved reliable, and robust PLS equations were proposed for this alveograph parameter. These prediction equations could be of interest to select for high values of W in the mid generations of breeding.

From multilocation trials involving 125 cultivars of wheat of mainly French and European origin four tests - protein content, Pelshenke, modified Zeleny and the mixograph - were used to establish six selection indices. Three of these indices - IW1, IW2 and IW3 - were calculated in order to evaluate the genetic potentiality of the lines for dough strength as given by the Chopin alveograph. The indices IV1, IV2 and IV3 were established to evaluate loaf volume as measured by the French bread-making standard. A quality index IQ was calculated from the allelic effects of the high-molecular-weight (HMW) subunits of glutenin from 195 cultivars assessed by the Chopin alveograph and the Pelshenke test. Comparison of the relative efficiency of each of the six indices to the individual tests revealed the superiority of the indices over one or several technological parameters. The six selection indices and the quality index were compared using 30 very diverse F4 lines. Their ability to retain the good quality lines is discussed in particular.

Recombinant inbred lines (RILs) derived by single plant descent to F8 from a hybrid of Anza, a low-quality cultivar, and Cajeme 71, a high-quality cultivar, differed in alleles at three high-molecular-weight glutenin (HMW-glu) seed storage protein loci. The 48 RILs were classified by SDS-PAGE for the Anza alleles Glu-Alc (null), Glu-B1b (subunits 7 + 8), and Glu-D1a (subunits 2 + 12) and for Cajeme 71 alleles Glu-A1a (sub-unit 1), Glu-B1I (subunits 17 + 18), and Glu-D1d (subunits 5 + 10). All RILs and parents were grown in a replicated field trial with three levels of nitrogen (N) fertilization. Additive and additive x additive gene effects for the three loci were detected by orthogonal comparisons of means for each of six wheat end-use quality traits. Each HMW-glu genotype was represented by three to ten RILs so that variability among RILs within each HMW-glu genotype could be examined. N effects were consistently small. All traits except flour yield were highly correlated with predictor traits studied earlier. Flour protein content, baking water absorption, dough mixing time, bread loaf volume, and bread loaf crumb score were all correlated, suggesting similar gene control for these traits; however, specific additive locus contributions were evident: αB for flour yield; αB and αD for flour protein; and αB for absorption, but differing in sign; all three loci for mixing time, but αB was negative; and all three loci were positively associated with loaf volume. Digenic epistatic effects were significant for flour yield (αAD), flour protein (αAB), and absorption and mixing time (αAD, αBD). Only flour yield showed a trigenic epistatic effect. Six of seven epistatic effects were negative, thus showing how progress in breeding for high quality may be impeded by interaction of genes which, by themselves, have strong positive additive effects. Considerable genetic variance among RILs within a HMW-glu genotype was detected for all traits, and the summation of α effects accounted for a mean of 13% of the parental differences for the six traits examined in this study. Clearly, further resolution of the genetics of wheat quality would be desirable from a plant breeding point of view.

L’éloignement génétique entre 33 lignées de blé tendre ayant servi à la production de 34 hybrides, a été estimé à partir de données biochimiques et à partir de l’étude des généalogies. Un dispositif multilocal a permis d’évaluer les hybrides et leurs parents, et de calculer les hétérosis pour le rendement, par rapport aux parents moyen et supérieur. Il n’apparaît aucune corrélation entre distances biochimiques et hétérosis, pas plus qu’entre le coefficient de parenté et l’hétérosis. L’intérêt de différentes mesures de distance pour la prédiction de l’hétérosis est discuté., Genetic divergence between 33 wheat lines used to produce 34 hybrids was estimated from biochemical data and a study of pedigrees. A multilocation experiment permitted evaluation of parents and hybrids, and the calculation of mid-parent and high-parent heterosis (table I). There was no correlation, either between biochemical distances and heterosis, or between coefficients of parentage according to Malecot and heterosis (fig 1, tables II and III). The use of different distances for heterosis prediction has been discussed.

La diversité génétique existant entre des lignées de blé tendre a été estimée à partir de données biochimiques (électrophorèse des protéines de réserve du grain), de caractères agronomiques et morphologiques et à partir de l’étude de leurs généalogies. Ces données ont permis le calcul de distances biochimiques et agromorphologiques, à l’aide des formules de distances du χ2 et absolue, et des coefficients de parenté selon Malecot. Il est apparu que chacune de ces distances donne une image différente de la diversité au niveau génétique. De plus, la prudence quant à l’utilisation des généalogies déclarées s’est avérée indispensable., Genetic diversity between wheat lines was estimated from biochemical data (storage, protein electrophoresis), measures of agronomic and morphological traits and the study of pedigrees. These data enabled the calculation of biochemical and agromorphological distances with the χ2 and absolute formulas, and of coefficients of parentage according to Malecot. It appears that every distance gives a different representation of genetic diversity, as these distances are in no way correlated. Pedigrees have to be considered with caution, as glutenin electrophoregrams of some lines do not agree with those of their alleged parents.

Meningiomas infrequently develop in children, and their clinical picture is somewhat different than in adults. We describe here a case of a meningioma in a 9-year-old girl unusual in two aspects. Firstly, it arose from the cavernous sinus what is exceptional in children. Secondly, despite the big tumor mass the child was almost asymptomatic. The only symptoms at presentation were a slight facial asymmetry and minimal laterodeviation of her mandible. Those symptoms had not been noticed by her parents and were detected during careful routine dental examination. The clinical course was quite aggressive and several neurosurgical interventions were necessary. This case underlines the importance of careful medical and dental examination during routine checkup consultations and undertaking necessary diagnostic procedures aimed at elucidating of all detected, even minimal abnormalities.

International audience; RGK (Rad-Gem-Rem) GTPases have been described as potent negative regulators of the Ca(2+) influx via high-threshold voltage-activated Ca(2+) channels. Recent work, mostly performed on Ca(V)1.2 Ca(2+) channels, has highlighted the crucial role played by the channel auxiliary Ca(V)beta subunits and identified several GTPase and beta-subunit protein domains involved in this regulation. We now extend these conclusions by producing the first complete characterization of the effects of Gem, Rem, and Rem2 on the neuronal Ca(V)2.1 Ca(2+) channels expressed with Ca(V)beta(1) or Ca(V)beta(2) subunits. Current inhibition is limited to a decrease in amplitude with no modification in the voltage dependence or kinetics of the current. We demonstrate that this inhibition can occur for Ca(V)beta constructs with impaired capacity to induce current potentiation, but that it is lost for Ca(V)beta constructs deleted for their beta-interaction domain. The RGK C-terminal last approximately 80 amino acids are sufficient to allow potent current inhibition and in vivo beta-subunit/Gem interaction. Interestingly, although Gem and Gem carboxy-terminus induce a completely different pattern of beta-subunit cellular localization, they both potently inhibit Ca(V)2.1 channels. These data therefore set the status of neuronal Ca(V)2.1 Ca(2+) channel inhibition by RGK GTPases, emphasizing the role of short amino acid sequences of both proteins in beta-subunit binding and channel inhibition and revealing a new mechanism for channel inhibition.

The high-molecular-weight glutenin subunits (HMW glutenin), encoded by alleles at homoeologous lociGlu-A1,Glu-B1, andGlu-D1 on the long arms of chromosomes1A,1B, and1D of a set of F8 random recombinant inbred lines (RIL) derived from the bread wheat cross Anza × Cajeme 71, were classified by SDS-PAGE. Anza has poor breadmaking quality and HMW-glutenin subunits (Payne numbers) null (Glu-A1c), 7+8 (Glu-B1b), and 2+12 (Glu-D1a); Cajeme 71 has good quality and 1 (Glu-A1a), 17+18 (Glu-B1i), and 5+10 (Glu-D1d). The combinations of these alleles in the RIL were examined for associations with grain yield and four indicators of grain quality - protein content, yellowberry, pearling index, and SDS sedimentation volume. Data were obtained from a field experiment with three nitrogen fertilization treatments on 48 RIL and the parents. Orthogonal partitioning of the genetic variance associated with the three HMW glutenin subunit loci into additive and epistatic (digenic and trigenic) effects showed strong associations of these loci with grain yield and the indicators of quality; however, the associations accounted for no more than 25% of the differences between the parents. Genetic variance was detected among the RIL, which had the same HMW glutenin genotype for all traits. Epistatic effects were absent for grain yield and yellowberry, but were substantial for grain protein content, pearling index, and SDS sedimentation volume. All three loci had large single-locus additive effects for grain yield, protein, and SDS sedimentation volume. Yellowberry was largely influenced byGlu-B1 andGlu-D1, whereas pearling index was associated withGlu-A1 andGlu-B1. Even though the observed associations-of effects of HMW glutenin loci with the quantitative characters were small relative to the total genetic variability, they are of considerable importance in understanding the genetics of wheat quality, and are useful in the development of new wheat varieties with specific desired characteristics.

Single-nucleotide polymorphisms (SNPs) constitute an abundant source of DNA polymorphisms, which have been successfully used to identify loci that are associated with a particular phenotype. Additionally, such markers could be efficiently used in combination with doubled haploid technology to improve the efficiency of breeding programmes. Information on such markers in plants is still scarce. For bread wheat, SNP data are restricted to a few genes. This can be explained by the hexaploidy of Triticum aestivum which makes SNP discovery difficult. We developed a novel method for SNP discovery in bread wheat. The strategy is based on the development of highly specific PCR-primers, which were used to sequence 27 lines. SNPs were discovered from sequence alignment data. Some SNPs were identified by mass spectrometry in a collection of 113 lines, which were both evaluated for agronomic traits and genotyped at 42 neutral microsatellite loci. Traits investigated include: protein content, the quantity of high-molecular-weight glutenins and that of the GluBx subunit. The 42 markers were used to infer population structure, which was included in linear models for association studies. The results of this preliminary study showed 89 SNPs in approximately 20 kbp, i.e., one SNP every 223 bp on average. Six SNPs were genotyped: three were located along the sequence of Glu-B1-1, while three non-synonymous SNPs were located along the sequence of the B homoeologous gene coding for SPA (Storage Protein Activator). The SNPs from Glu-B1-1 had a significant effect on the studied variables, whereas those of SPA had no effect. Such results might indicate that some haplotypes for Glu-B1-1 are linked to higher protein content, through an increased amount of high-molecular-weight glutenins, especially the GluBx subunit.

The mechanical properties of the combined outer layers from near-isogenic wheats differing by hardness were determined. Results from traction tests showed significant differences between the isogenic lines, outer layers from grains of the soft type showing higher extensibility. Determination of the mechanical properties of the corresponding component tissues revealed significant differences between the isolated tissues from soft or hard wheat grains. It also allowed analysis of their respective contribution to the properties of the combined peripheral tissues using a simulation of their rupture as unseparated tissues. According to the results, if the component layers displayed similar maximum lineic force to rupture, the rupture of combined outer layers occurs when the least extensible individual tissue breaks. The major cell wall biochemical components of the combined outer layers and of their component tissues were analysed. The phenolic acid composition of soft wheat pericarp contained more ferulic acid in either monomeric or polymeric forms than the pericarp from hard wheat. Arabinoxylans in walls of the soft wheat pericarp appeared 1.6 times more cross-linked by ferulic acid dehydrodimers than walls of hard wheat. These differences in arabinoxylan cross-linking may explain the observed differences in pericarp mechanical properties.

International audience; Background and Aims Dynamic management (DM) of genetic resources aims at maintaining genetic variability between different populations evolving under natural selection in contrasting environments. In 1984, this strategy was applied in a pilot experiment on wheat (Triticum aestivum). Spatio-temporal evolution of earliness and its components (partial vernalization sensitivity, daylength sensitivity and earliness per se that determines flowering time independently of environmental stimuli) was investigated in this multisite and long-term experiment. Methods Heading time of six populations from the tenth generation was evaluated under different vernalization and photoperiodic conditions. Key Results Although temporal evolution during ten generations was not significant, populations of generation 10 were genetically differentiated according to a north–south latitudinal trend for two components out of three: partial vernalization sensitivity and narrow-sense earliness. ConclusionsIt is concluded that local climatic conditions greatly influenced the evolution of population earliness, thus being a major factor of differentiation in the DM system. Accordingly, a substantial proportion (25 %) of genetic variance was distributed among populations, suggesting that diversity was on average conserved during evolution but was differently distributed by natural selection (and possibly drift). Earliness is a complex trait and each genetic factor is controlled by multiple homeoalleles; the next step will be to look for spatial divergence in allele frequencies.

Wheat grain hardness is a major factor affecting the milling behaviour and end-product quality although its exact structural and biochemical basis is still not understood. This study describes the development of new near-isogenic lines selected on hardness. Hard and soft sister lines were characterised by near infrared reflectance (NIR) and particle size index (PSI) hardness index, grain protein content, thousand kernel weight and vitreousness. The milling behaviour of these wheat lines was evaluated on an instrumented micromill which also measures the grinding energy and flour particle size distribution was investigated by laser diffraction. Endosperm mechanical properties were measured using compression tests. Results pointed out the respective effect of hardness and vitreousness on those characteristics. Hardness was shown to influence both the mode of fracture and the mechanical properties of the whole grain and endosperm. Thus, this parameter also acts on milling behaviour. On the other hand, vitreousness was found to mainly play a role on the energy required to break the grain. This study allows us to distinguish between consequences of hardness and vitreousness. Hardness is suggested to influence the adhesion forces between starch granules and protein matrix whereas vitreousness would rather be related to the endosperm microstructure.

Calcium influx into cardiac myocytes via voltage-gated Ca channels is a key step in initiating the contractile response. During prolonged depolarizations, toxic Ca(2+) overload is prevented by channel inactivation occurring through two different processes identified by their primary trigger: voltage or intracellular Ca(2+). In physiological situations, cardiac L-type (Ca(V)1.2) Ca(2+) channels inactivate primarily via Ca(2+)-dependent inactivation (CDI), while neuronal P/Q (Ca(V)2.1) Ca(2+) channels use preferentially voltage-dependent inactivation (VDI). In certain situations however, these two types of channels have been shown to be able to inactivate by both processes. From a structural view point, the rearrangement occurring during CDI and VDI is not precisely known, but functional studies have underlined the role played by at least 2 channel sequences: a C-terminal binding site for the Ca(2+) sensor calmodulin, essential for CDI, and the loop connecting domains I and II, essential for VDI. The conserved regulation of VDI and CDI by the auxiliary channel beta subunit strongly suggests that these two mechanisms may use a set of common protein-protein interactions that are influenced by the auxiliary subunit. We will review our current knowledge of these interactions. New data are presented on L-P/Q (Ca(V)1.2/Ca(V)2.1) channel chimera that confirm the role of the I-II loop in VDI and CDI, and reveal some of the essential steps in Ca(2+) channel inactivation.

Starting from a comparative study of different Ca2+ chelators on the G-protein-induced inhibition of the CaV2.1 Ca channels, we demonstrate that BAPTA and DM-nitrophen are able to interact, in a Ca2+- and lipid-dependent manner, with phospholipid monolayers. Critical insertion pressure and sensitivity to charged lipids indicated that insertion in the lipid film may occur in biological membranes as those found on Xenopus oocytes. This novel property is not found for EGTA and EDTA and may participate to the unusual ability of BAPTA-related molecules to chelate Ca2+ ions in the very close vicinity of the plasma membrane, where most of the Ca2+-dependent signalling triggered by voltage-gated Ca2+ currents occurs.

Earliness, an adaptative trait and factor of variation for agronomic characters, is a major trait in plant breeding. Its constituent traits, photoperiod sensitivity (PS), vernalization requirement (VR) and intrinsic earliness (IE), are largely under independent genetic controls. Mapping of major genes and quantitative trait loci (QTL) controlling these components is in progress. Most of the studies focusing on earliness considered it as a whole or through one (or two) of its components. The purpose of this study was to detect and map QTL for the three traits together through an experimental design combining field trials and controlled growth conditions. QTL were mapped in a population of F(7) recombinant inbred lines derived by single-seed descent from a cross between two French varieties, 'Renan' and 'Recital'. A map was previously constructed, based on 194 lines and 254 markers, covering about 77% of the genome. Globally, 13 QTL with a LOD2.5 were detected, of which four control PS, five control VR and four control IE. Two major photoperiod sensitive QTL, together explaining more than 31% of the phenotypic variation, were mapped on chromosomes 2B and 2D, at the same position as the two major genes Ppd-B1 and Ppd-D1. One major VR QTL explaining (depending on the year) 21.8-39.6% of the phenotypic variation was mapped on 5A. Among the other QTL, two QTL of PS and VR not referenced so far were detected on 5A and 6D, respectively. A VR QTL already detected on 2B in a connected population was confirmed.

The catch of stereotypes X-ray introduces a conical projection phenomenon which introduce errors from 1 to 5 millimetres. To obtain the real position of anatomical point with precision, we show an original method of co-ordinate 3D calculation which takes account of system radiographic dimensions. A point of space is located compared to the frame of reference of center O (medium of the segment materialized by olives). The frontal stereotype is selected like image of reference after having placed, a 4 mms metal ball on midface of patient. The side stereotype is obtained while making turn the patient of 90 degrees. The axial stereotype is obtained by rotation of the head, around horizontal olives axis. We suppose that the Source-Stereotype unit turns around the patient's head (considered fixed). The protocol comprises a stage of catch of stereotypes X-ray, a stage of digitalization of the sights and initialization of the system and a stage of measurement itself. We describe the setting in equation of real co-ordinate point determination. We apply to the apparent coordinate, the correction formulas we obtain the real co-ordinates of the point.

Occlusion through successive phases of dental eruption was the concern of many authors. So that the progressive installation of occlusion is made harmonious way, it is necessary that the dental eruption sequences proceed correctly. The authors have studied rhythm appearance of permanent teeth, and they have determined the average eruption age of canines, first, second premolar and second molar. The results are given for the 574 children of the sample and following to the sex.

The keratin 18 (K18) gene is expressed at a normal level in cells of nontumorigenic clones derived from the SW613-S human colon carcinoma cell line, but is overexpressed in cells of tumorigenic clones. A high level of expression was also found in the cells from 10 of 15 other human colon carcinoma cell lines. The expression of the gene is downregulated in differentiating Caco-2 cells, resulting in a normal expression level. Determination of K18 mRNA half-life in growing and confluent Caco-2 cells indicated that this downregulation does not take place at a posttranscriptional level. The density of RNA polymerase molecules on the K18 gene, as measured in nuclear run-on experiments, is the same in growing and confluent Caco-2 cells, but the rate of synthesis of K18 transcripts in confluent Caco-2 cells, as determined by in vivo pulse-labeling, is 35% of that in growing cells. Nuclear run-on experiments carried out with nuclei prepared from growing or confluent Caco-2 cells treated with 5,6-dichloro-1-beta-D-ribofuranosyl benzimidazole (DRB) indicated that a reduction in both the initiation and elongation rates of RNA polymerase molecules occurs on the K18 gene in confluent Caco-2 cells. This leads to a decreased rate of K18 transcript production with no reduction in the polymerase density on the gene. Evidence is provided that the mechanisms responsible for the differential expression of the K18 gene between tumorigenic and nontumorigenic SW613-S cells and between growing and differentiating Caco-2 cells share some similarities.

Since 1925, the work of BROADBENT and the invention of the cephalostat (in 5), radiographic cephalometry has enabled us to have a detailed knowledge of craniofacial structures, and to better understand the form of the skull. At the same time it enabled us to understand the maxillo-facial growth and dental maturation. However, they have given rise to many controversies because of magnifying power and distortions. The question posed by magnification is still debated, even if some authors have attempted to solve the problems brought forward by distortion effect which seem to neglect radiographic conical projection. This study aims to appreciate not only the magnifying and its distortion consequences but equally the effect of conical X ray. The authors make use of mathematical equations and attempt to bring forward a correction based on 3D projection.

Stargazin or [gamma]2, the product of the gene mutated in the stargazer mouse, is a homologue of the [gamma]1 protein, an accessory subunit of the skeletal muscle L-type Ca2+ channel. [gamma]2 is selectively expressed in the brain, and considered to be a putative neuronal Ca2+ channel subunit based mainly on homology to [gamma]1. Two new members of the [gamma] family expressed in the brain have recently been identified: [gamma]3 and [gamma]4. We have co-expressed, in Xenopus oocytes, the human [gamma]2, [gamma]3 and [gamma]4 subunits with the P/Q-type (Ca(V)2.1) Ca2+ channel and different regulatory subunits ([alpha]2-[delta]; [beta]1, [beta]2, [beta]3 or [beta]4). Subcellular distribution of the [gamma] subunits confirmed their membrane localization. Ba2+ currents, recorded using two-electrode voltage clamp, showed that the effects of the [gamma] subunits on the electrophysiological properties of the channel are, most of the time, minor. However, a fraction of the oocytes expressing [beta] subunits displayed an unusual slow-inactivating Ba2+ current. Expression of both [beta] and [gamma] subunits increased the appearance of the slow-inactivating current. Our data support a role for the [gamma] subunit as a brain Ca2+ channel modulatory subunit and suggest that [beta] and [gamma] subunits are involved in a switch between two regulatory modes of the P/Q-type channel inactivation.

Phosphorylation/dephosphorylation processes are known to control the activity of several transcription factors. The nutrition-dependent expression of sucrase-isomaltase and Na+/glucose co-transporter 1, two proteins implicated in the intestinal absorption of glucose, has been shown to be closely related to modifications of hepatocyte nuclear factor 1 (HNF1) activity. This study was conducted to determine whether phosphorylation/dephosphorylation processes could control HNF1 activity. We show that expression of the gene encoding sucrase-isomaltase is inhibited in the enterocytic Caco-2 clone TC7 by okadaic acid at a concentration that is known to inhibit protein phosphatases 1/2A and that does not affect cell viability. At the same concentration, phosphorylation of the HNF1alpha and HNF1beta isoforms is greatly enhanced and their DNA-binding capacity is decreased. The phosphorylation state of HNF1beta isoforms directly affects their DNA-binding capacity. In contrast, the decreased DNA-binding activity of the HNF1alpha isoforms, which was observed after the inhibition of protein phosphatases 1/2A, is due to a net decrease in their total cellular and nuclear amounts. Such an effect results from a decrease in both the HNF1alpha mRNA levels and the half-life of the protein. This is the first evidence for the implication of protein phosphatases 1/2A in the control of the activity of HNF1 isoforms. Moreover, these results emphasize a physiological role for the balance between phosphatases and kinases in the nutrition-dependent regulation of HNF1-controlled genes.

Telosomic stocks have been extensively used to map genes to chromosome arms and to determine gene-to-centromere genetic distances. It has been suggested that if a chromosome arm is present as a telosome, recombination frequencies will be drastically reduced in the centromeric region. However, previous studies have not considered the bias in recombination estimates due to selection against aneuploid gametes produced by failure of pairing at the first meiotic division. Formulas are derived here for adjusting recombination estimates for this bias. Adjusted recombination frequencies between markers located on both sides of the centromeres are analyzed in three different pairs of wheat (Triticum aestivum) isogenic segregating populations involving bibrachial and telocentric chromosomes. Recombination frequencies estimated from crosses involving telocentric chromosomes were not significantly different from recombination frequencies estimated from isogenic crosses involving bibrachial chromosomes. The implications of the present findings for karyotype evolution, and specifically for Robertsonian fissions and fusions, are discussed.