No / Most cancer cells use aerobic glycolysis to fuel their growth. The enzyme lactate dehydrogenase-A (LDH-A) is key to cancer’s glycolytic phenotype, catalysing the regeneration of nicotinamide adenine dinucleotide (NAD+) from reduced nicotinamide adenine dinucleotide (NADH) necessary to sustain glycolysis. As such, LDH-A is a promising target for anticancer therapy. Here we ask if the tumour suppressor p53, a major regulator of cellular metabolism, influences the response of cancer cells to LDH-A suppression. LDH-A knockdown by RNA interference (RNAi) induced cancer cell death in p53 wild-type, mutant and p53-null human cancer cell lines, indicating that endogenous LDH-A promotes cancer cell survival irrespective of cancer cell p53 status. Unexpectedly, however, we uncovered a novel role for p53 in the regulation of cancer cell NAD+ and its reduced form NADH. Thus, LDH-A silencing by RNAi, or its inhibition using a small-molecule inhibitor, resulted in a p53-dependent increase in the cancer cell ratio of NADH:NAD+. This effect was specific for p53+/+ cancer cells and correlated with (i) reduced activity of NAD+-dependent deacetylase sirtuin 1 (SIRT1) and (ii) an increase in acetylated p53, a known target of SIRT1 deacetylation activity. In addition, activation of the redox-sensitive anticancer drug EO9 was enhanced selectively in p53+/+ cancer cells, attributable to increased activity of NAD(P)H-dependent oxidoreductase NQO1 (NAD(P)H quinone oxidoreductase 1). Suppressing LDH-A increased EO9-induced DNA damage in p53+/+ cancer cells, but importantly had no additive effect in non-cancer cells. Our results identify a unique strategy by which the NADH/NAD+ cellular redox status can be modulated in a cancer-specific, p53-dependent manner and we show that this can impact upon the activity of important NAD(H)-dependent enzymes. To summarise, this work indicates two distinct mechanisms by which suppressing LDH-A could potentially be used to kill cancer cells selectively, (i) through induction of apoptosis, irrespective of cancer cell p53 status and (ii) as a part of a combinatorial approach with redox-sensitive anticancer drugs via a novel p53/NAD(H)-dependent mechanism.

Ces travaux de thèse ont porté sur le développement de nouveaux engrais à relargage contrôlé grâce à la mise en œuvre d’un procédé de mechanosynthèse à partir de mélanges contenant des composés lamellaires soit naturels (montmorillonite, talc et chrysotile) soit synthétiques (les Hydroxydes Doubles Lamellaires (HDL) à base de Mg, d’Al et de Fe) et de monohydrogénophosphate de potassium. Ce sel est déjà utilisé en agriculture en tant que fertilisant conventionnel. Toutefois sa forte solubilité en solution aqueuse induit des pertes importantes lors de l’épandage via des procédés de lixiviation, de volatilisation ou encore de fixation dans les sols, limitant ainsi l’efficacité des nutriments pour les plantes. Il est alors nécessaire d’en utiliser des quantités excessives pour observer une efficacité en agriculture. Aussi la principale alternative est de contrôler l’apport en éléments venant d’une part du sel soluble mais également des constituants chimiques des matrices lamellaires impliquées. Une telle approche pourrait réduire les coûts en permettant une fertilisation accrue tout en en diminuant la solubilité des ions impliqués. La méthode utilisée consiste à broyer les réactifs ensemble en modifiant les conditions de broyage utilisées. Afin d’évaluer les modifications structurales induites par le broyage, les échantillons obtenus sont caractérisés à l’aide de différentes techniques de caractérisation du solide, en fonction des éléments chimiques impliqués. La diffraction des rayons X (PXRD), la microscopie électronique à balayage couplé avec un analyseur (SEM-EDX) et les méthodes spectroscopiques SSNMR, FTIR, RAMAN, RPE…) se sont avérées pertinentes pour réaliser le suivi des réactions de mechanosynthèse et mettre en évidence une amorphisation des matrices précruseurs et éventuellement la formation de nouvelles phases cristallisées. La microscopie montre sytématiquement une modification importante de la taille des particules avec perte de la morphologie des matériaux précurseurs et parfois apparition de nouveaux cristaux de forme bien définie ayant une composition chimique différente. Grâce à la spectroscopie RMN à l’état solide il est possible de mettre en évidence de fortes modifications de l’environnement chimique après mechanosynthèse, suggérant la formation de composés métastables impliquant des cations métalliques issus des phases lamellaires, du phosphore et de l’oxygène. Les composés obtenus ont ensuité été étudiés dans des conditions de relargage mettant en évidence des propriétés de realargage contrôlé quelle que soit la matrice lamellaire précurseur impliquée dans le procédé. La vitesse de relargage des nutriments est influencée par la nature et la composition chimique de la matrices de départ, sachant qu’en fonction de leur composition chimique des produits différents peuvent être formés. / The present work describes the development of slow release fertilizers from the mechanochemical activation of of natural (montmorillonite, talc, chrysotile) and synthetic (Layered Double Hydroxides (LDH) MgAl and MgFe) lamellar matrix mixtures with potassium monohydrogen phosphate. This salt is used in agriculture as a conventional fertilizer and is highly soluble in aqueous solution, which implies large losses due to leaching processes, volatilization or even fixation in the soil, limiting the efficiency of the nutrients for the plants. Due to these characteristics, there is a need to apply large quantities of these products in agriculture. Therefore, the main idea is to control the supply of both the elements coming from the soluble salt as well as the constituting elements of the lamellar matrices. Such approach could reduce costs with exacerbated fertilization, potentiating the use of the products and decreasing the solubility of the ions involved. The methodology used basically consists of the milling of the reagents varying the processing conditions. For the characterization of the samples, several techniques were used according to the nature of the compounds involved. Particularly, PXRD, SEM / EDX and spectroscopic (SSNMR, FTIR, RAMAN, EPR…) techniques proved to be highly efficient for the monitoring of the mechano-chemical reaction, and to highlight the amorphization of the precursors and/or the formation of a distinct crystalline phase. SEM/EDX showed after the mechanochemical activation the changes in particle size, the disappearance of precursor morphologies, and the formation of particles with distinct morphologies and different chemical composition. Using solid state NMR measurements significant changes in the chemical environments involved were evidenced, suggesting the formation of metastable compounds between metal cations from the lamellar matrices, phosphorus and oxygen, as well as other possible compounds as products. After the mechanochemical reaction, in the nutrient release assays, the slow release behavior was observed for all the matrices analyzed. The release rate can be influenced by the chemical composition of the starting matrices, since each matrix can produce similar and distinct products, for example, SiO2 from natural clays which is not possible in the LDH products.

Made available in DSpace on 2016-06-02T20:19:20Z (GMT). No. of bitstreams: 1 DissWHBV.pdf: 1262408 bytes, checksum: 46ed12e3f59bfa6a851e19038a1181ec (MD5) Previous issue date: 2004-12-14 / Universidade Federal de Sao Carlos / The purpose of this study was to evaluate relative the physiological adaptation the activities of enzymes Lactate Dehidrogenase LDH (glycolytic) e Citrate Synthase CS (oxidative) and to the Anaerobic Threshold (AT), to the exercise in treadmill in rats submitted to the photostimulation for low-intensity laser (780 ηm) in the main participant muscles of the march. Fifty-four male Wistar rats had been part of the study. These animals were divided in four groups: Two had remained in rest (1) GRC, being one of them irradied (2) GRL, and other two were submitted to an aerobic treadmill training program during 5 weeks and to a multistage treadmill test of increasing intensity (3) GEC, being one of them irradied (4) GEL. The irradiation for infra-red laser (780 ηm) was made daily in number of four (quadriceps, maximum glúteo, soleus, tibialis anterior) in each back leg of the animals, totalizing 8 applications for animal/day, using (dose, 3,8 J/cm2; power, 15 mW; time, 10 s, continuous) during 5 weeks consecutives. The multistage treadmill tests of increasing intensity were made once a week totalizing 5 evaluation, in order to obtain blood samples for determination of the AT. In the analyses electrophoretics and spectrophotometic of the LDH and CS muscles samples (soleus, TA and cardiac) were removed 48 hours after the last exercise bout. The laser to promote increase in the oxidative metabolism of 2% a 78%, the exercise of 18% a 75%, and action combined of 43% a 92%; Apparent systemic action of the laser was detected in cardiac muscle with increase in the activity of the CS and reduction of the LDH. The group GEC and GEL showed increase in the maximum speed, in the speed corresponding to the AT and a trend reduction of the blood lactate concentration during the training period. However, no significant difference occurred between two groups though the GEL had shown higher values. These data suggest that the aerobic treadmill-training partner to the low-intensity laser can to promote physiological adaptation in the direction of increase oxidative capacity in the animals, represented by increase of the CS, reduction of the LDH and by the higher degree of effort to reach the Anaerobic Threshold. This similarity has a utility therapeutic practical. / O presente estudo avaliou as adaptações fisiológicas relativas as atividades das enzimas Lactato Desidrogenase - LDH (glicolítica) e Citrato Sintase - CS (oxidativa) e ao Limiar de Anaerobiose (LA), ao exercício em esteira em ratos submetidos à fotoestimulação por laser de baixa intensidade (780nm) nos principais músculos participantes da marcha. Fizeram parte do estudo 54 ratos machos, jovens (30 dias), Wistar, que foram divididos em quatro grupos: dois permaneceram em repouso: (1) GRC, sendo um deles irradiado (2) GRL, e dois foram submetidos a um protocolo de treinamento aeróbio em esteira por 5 semanas e a testes de esforços crescentes (3) GEC, sendo um deles irradiado (4) GEL. A irradiação por laser infravermelho foi feita, diariamente, em número de quatro: quadríceps, glúteo máximo, Tibial Anterior (TA) e sóleo, em cada pata traseira, totalizando 8 aplicações por animal/dia, sob os parâmetros: Dose: 3,8 J/cm2, Potência: 15 mW, Tempo: 10 segundos, modo contínuo, durante 5 semanas consecutivas. Os testes de esforço crescente foram realizados, uma vez por semana, totalizando 5 avaliações durante as quais foram obtidas amostras de sangue visando a determinação do LA. Nas análises eletroforéticas e espectrofotométricas da LDH e CS, foram utilizadas frações de músculo TA, sóleo e cardíaco retiradas 48 horas após a última sessão de exercício. O laser provocou aumentos do metabolismo aeróbio de 2% à 78%, o exercício de 18% à 75% e suas ações combinadas de 43% à 92%. Aparente ação sistêmica do laser foi detectada em músculo cardíaco, com aumento da atividade da CS e diminuição da atividade LDH. Os grupos GEC e GEL exibiram aumento na velocidade máxima, LA deslocado para um nível de maior esforço e uma ligeira tendência de redução do lactato sérico no decorrer das avaliações. Entretanto, não houve diferenças estatisticamente significantes entre os grupos, apesar do GEL ter exibido maiores valores. Esses dados sugerem que o treinamento aeróbio em esteira associado ao laser de baixa intensidade possa acarretar adaptações fisiológicas no sentido de aumento na capacidade oxidativa dos animais representada pelo aumento na atividade da CS, diminuição da LDH e maior grau de esforço para a obtenção do LA, fato este, de grande utilidade na prática terapêutica.

"Alzheimer’s disease (AD) is a neurodegenerative disorder that currently affects an estimated 4.2 million to 5.8 million Americans. Although the cause of AD is not fully known, the current working model proposes that amyloid precursor protein (APP) is unnaturally cleaved by beta and gamma secretases to form the highly neurotoxic peptide beta-amyloid (Aâ) which engages cell surface receptors to cause cell death through a series of events involving oxidative stress and apoptosis. An in vitro model for AD uses cultured human SHSY-5Y (commonly abbreviated SHSY) neuroblastoma cells treated with Yankner peptide, an 11 amino acid peptide representing Aâ residues 25-35 that strongly binds receptor. Treatment of SHSY cells with 20 µM Yankner peptide strongly induces cellular apoptosis. Synthetic peptide human ependymin-1 (hEPN-1) is a derivative of a naturally occurring protein within the human brain, previously shown by our laboratory to upregulate antioxidative enzymes in SHSY cells, and AP-1 transcription factor associated with long-term memory formation. Since hEPN-1 has anti-oxidative potential as a therapeutic, we hypothesized that hEPN-1 can reverse the neurotoxic effects of Yankner peptide treatment of cultured human SHSY neuronal cells. Microtiter dishes were plated with SHSY cells under control conditions (no Yankner peptide), in the presence of 20 µM Yankner peptide, or in the presence of Yankner peptide plus various concentrations of hEPN-1 therapeutic, then cultured for 3 days to 80% confluency. Unattached dying cells were gently washed away, then the residual cells were monitored by measuring cell number, cell viability (Trypan blue exclusion), LDH activity per mg protein (an indirect measure of cell viability), and nuclear blebbing (a measure of apoptosis). Statistical significance was determined using a One Way ANOVA under the LSD stringency, using SPSS. In three independent trials, average cell numbers per microtiter well decreased 44.7% (from 3.11 x 105 to 1.72 x 105) in the presence of 20 µM Yankner peptide (p < 0.05 compared to control), were 2.73 x 105 when 75 µM hEPN-1 was added simultaneously with Yankner (p < 0.05 compared to Yankner), and were 2.96 x 105 when 75 µM hEPN-1 was added 24 hrs post-Yankner (p < 0.05 relative to Yankner alone). The control mean was not statistically distinguishable from either of the hEPN-1-treated samples (p = 0.220 and p = 0.671, respectively). With respect to the trypan blue data, in three independent trials, the mean percent viable cells (excluding trypan blue) decreased 41.0% (from 68.7% to 40.5%) in the presence of 20 µM Yankner peptide (p < 0.001 relative to control), was 60.7% when 75 µM hEPN-1 was added simultaneously with Yankner (p < 0.001 relative to Yankner alone), and was 61.4% when 75 µM hEPN-1 was added 24 hrs post-Yankner (p < 0.001 relative to Yankner alone). The control mean was not statistically distinguishable from either of the hEPN-1-treated samples (p = 0.013 and 0.03, respectively). In the LDH activity experiments, in four independent trials, the average LDH OD decreased 80.8% (from 0.47 to 0.09) in the presence of 20 µM Yankner peptide (p < 0.001 relative to control), was 0.47 when 75 µM hEPN-1 was added simultaneously with Yankner (p < 0.001 relative to Yankner alone), and was 0.48 when 75 µM hEPN-1 was added 24 hrs post-Yankner (p < 0.001 relative to Yankner alone). The control mean was not statistically distinguishable from either of the hEPN-1-treated samples (p = 0.174 and 0.479, respectively). Although previous reports in the literature indicated LDH expression is constitutive in SHSY cells (thus its activity is an indirect measure of cell numbers or viability), it was possible the hEPN-1 treatments upregulated LDH activity. So to ensure our observed changes in LDH activity levels did not represent changes per unit protein, the LDH activity values were divided by the mg of protein present in the sample, and all four experimental samples were statistically indistinguishable (p values = 0.184, 0.995, 0.872, respectively, relative to control). In the nuclear blebbing experiments, in five independent trials, the mean percent blebbed nuclei (a measure of apoptosis) doubled from 7.5% to 16.0% in the presence of 20 µM Yankner peptide (p < 0.001 relative to control), was 6.7% when 75 µM hEPN-1 was added simultaneously with Yankner (p < 0.001 relative to Yankner alone), and was 6.5% when 75 µM hEPN-1 was added 24 hrs post-Yankner (p < 0.001 relative to Yankner alone). The decreased apoptosis observed in the hEPN-1-treated samples was however, not statistically significant (p = 0.381 and 0.279, respectively). Overall, the data suggest that hEPN-1 can protect human neuronal cells from Yankner-induced cell death, whether added simultaneous to the insult, or 24 hrs post. Because the therapeutic can act 24 hrs post-insult, it may interfere with a late-stage apoptotic event. As there is currently no known drug that blocks Yankner-induced toxicity, the hEPN-1 therapeutic shows potential in combating the underlying apoptosis of Alzheimer’s disease."

L’intercalation de molécules organiques dans les Hydroxydes Doubles Lamellaires conduit à la formation d’hybrides organo-minéraux lamellaires aux propriétés originales. La valorisation de ces matériaux pour des applications diverses nécessite d’une part, le développement d’une méthode de synthèse simple et efficace pour garantir la pureté des hybrides, et d’autre part, d’établir les relations composition-structure (feuillet cationique, anion et eau interfoliaire). C’est pour atteindre ces deux objectifs, que nous avons menés les travaux présentés dans ce mémoire. La stratégie de synthèse adoptée dans ce travail de thèse nous a permis d’obtenir des taux d’intercalation meilleurs que ceux obtenus par les autres méthodes (coprécipitation, reconstruction, etc.) pour des molécules organiques simples (acides dicarboxyliques) ainsi que pour des molécules plus complexes (acides aminés et oligopeptides). Les acides aminés sont classés en trois groupes selon leur taux d’intercalation, qui est influencé par la chaîne latérale des acides aminés. Ainsi, la distance interfoliaire et les défauts d’empilements augmentent avec la longueur de la chaîne, alors que la diminution de la charge du feuillet contribue à la contraction du domaine interfoliaire et à une meilleure structuration du matériau, en lien avec l’orientation des anions. On peut noter que l’effet de la charge du feuillet sur la distance interfoliaire pour les hybrides est l’inverse de celui observé pour les anions inorganiques. L’hydratation du matériau joue également un rôle clé sur l’orientation des anions interfoliaires et la structuration du matériau. Ainsi, la déshydratation du matériau favorise les orientations couchées des anions en augmentant les interactions anion-feuillet, ce qui augmente la stabilité de l’hybride et favorise sa structuration. Nous avons également montré que la présence des groupements amine favorise les interactions anion-feuillet. Aussi, le changement d’orientation des acides aminés intercalés nécessite une exposition des matériaux à des humidités relatives plus élevées que pour les anions dicarboxylates. En outre, nous avons vérifié l’intercalation préférentielle des anions avec des densités de charge élevées. En conséquence, les acides aminés se retrouvent intercalés sous forme totalement déprotonée quelle que soit la charge du feuillet. Enfin, ce mémoire propose une ouverture sur la réactivité des hybrides synthétisés. Celle-ci est abordée au travers d’exemples portant sur la décomposition d’espèces en milieu confiné et sur l’interaction avec le CO2 atmosphérique / The intercalation of organic molecules within the interlayer domain of Layered Double Hydroxides leads to the formation of organo-mineral hybrids with original properties. The industrial applications of these materials requires on one hand to develop a simple and efficient method of synthesis to ensure a high purity of these hybrids, and on the other hand to establish their structure-composition relationships (cationic layer, anion, and interlayer water). These are the objectives that motivated the work presented in this manuscript. The strategy of synthesis adopted in this work, allowed us to obtain higher rates of intercalation than those obtained by other methods (coprecipitation, reconstruction, etc.), for simple organic molecules (dicarboxylic acids) as well as for more complex molecules (amino acids and oligopeptides). The amino acids are classified into three groups according to their rate of intercalation, which is influenced by the nature of their side chain. Additionally, the interlayer distance and stacking faults are influenced by the length of the molecular chain and by the anion orientation which in turn depends on the density charge of the layer. Interestingly, the effect of the density charge on the interlayer distance for the hybrids is the opposite of what is observed for the inorganic anions. The hydration state of the system plays also a key role in the reorientation of the interlayer anions and on the material structuring. In particular, the dehydration of the material promotes lying orientations of the interlayer anions in the order to maximize the anion-layer interactions. This enhances the stability of the material and reduces the number of stacking faults. We have also showed that the presence of amino groups strengthens the anion-layer interactions and the reorientation of the anions occurs at higher humidity compared to dicarboxylate anions. Furthermore, we have verified the preferential intercalation of anion species with high charge densities. Therefore, the intercalated amino acids are found totally deprotonated in the interlayer domain regardless of the layer charge density. Finally, the reactivity of the hybrids is probed through two examples, one dealing with the thermal decomposition of the intercalated anions in confined medium, and the other dealing with their interaction with atmospheric CO2

The genetic structure of 25 wild populations and five hatchery stocks from Czech Republic and Slovakia were analysed using mitochondrial (control region) and nuclear DNA (microsatellites, LDH-C1*) markers to elucidate the impact of stocking on central European populations of brown trout and to outline further management strategies. It seems that stocking practices have caused massive hybridisation between the Atlantic and Danube brown trout populations in the middle Danube basin and have led to a loss of among-population genetic variability in Slovakia and Moravia. Certain effect of stocking was detected also in the upper Danube, Vistula, Oder and Elbe River basins. However, the populations from the Elbe River basin keep certain level of among-population variability and seem to be less affected by stocking in comparison with the Danube River basin populations. There are some indications of late or post-Pleistocene penetration of the Atlantic basin trout to the Danube River basin. However, it is not clear to which extent the natural contact participated to the present distribution of Atlantic haplotypes and alleles in the Danube River basin. Samples from lower parts of the Danube River basin were therefore analysed using the same mitochondrial and microsatellite markers. Samples from Aegean Sea basin were included in order to reveal genetic variability of eastern Balkan populations and to estimate an impact of stocking in this area. Very low levels of introgression from Atlantic and other non-indigenous trout were found in the eastern Balkan populations. The genetic differentiation among the populations is substantially higher in this area compared to the central European populations. The populations in headwaters of the Otava River (Elbe River basin) were analysed using microsatellites in order to reveal origin of these populations and evaluate the current management strategies of brown trout in Šumava National Park and Protected Landscape Area. The analysed populations were substantially differentiated from the remaining Elbe River basin populations and there was also certain level of genetic structure within trout from the headwaters of the Otava River associated with isolation by a migration barrier and geographic distance. However, stocking with hatchery trout also contributed to the pattern of genetic variability. The population of Borová Lada hatchery, which is used for stocking in Šumava exhibited higher genetic variability compared to the wild populations and it seems to be of heterogeneous origin. Comparisons of the analysed populations with populations from other areas and results from other studies indicated that mtDNA haplotypes from the lower Danube River and southern Black Sea basins differ considerably from a subclade of the Danubian lineage consisting of haplotypes found so far in the most of the Danube River basin and in the Caspian and Aral Sea basins. The results thus evidence a complex evolutionary history of brown trout in the southern and western parts of the Black Sea basin.

Notre étude porte sur l’identification des mécanismes de sorption des ions (poly)molybdate et (poly)tungstate sur différents substrats : les hydroxydes doubles lamellaires (LDH) et les (hydr)oxydes de fer (hématite, goethite, akaganéite et lépidocrocite). La spectroscopie infrarouge en réflexion totale atténuée (ATR-FTIR) est l’une des rares méthodes à permettre l’analyse in situ et l’observation des phénomènes de sorption en temps réel directement sur les surfaces. Il est ainsi possible d’obtenir des informations sur la spéciation de surface et de connaitre la géométrie des espèces adsorbées (monodentate, bidentate, polymère, …). Nous avons ainsi pu déterminer la différence de réactivité entre les différents matériaux lors de la sorption. Un échange d’ion (sphère externe) impliquant les anions polyoxométalate a lieu avec les hydroxydes doubles lamellaires tandis que des complexes de sphère interne ont été observés sur les oxydes de fer, avec des géométries différentes selon la structure de surface du solide. Cette étude expérimentale a été complétée par différents calculs de spectres vibrationnels, réalisé par DFT ab initio, qui ont confirmé la géométrie de surface des espèces adsorbées observées par infra-rouge. / Our study focuses on the identification of (poly)molybdate and (poly)tungstate ions sorption mechanisms on various substrates : layered double hydroxides (LDH) and iron (hydr)oxide (hematite, goethite, akaganeite and lepidocrocite). Attenuated total reflection infrared spectroscopy (ATR-FTIR) is one of the few methods that allow in situ analysis and observation of sorption mechanisms in real time directly on surfaces. Thus, information on surface speciation and the geometry of the sorbed species (monodentate, bidentate, polyanion, …) can be obtained. We were able to determine the reactivity differences between the materials during the sorption. Ion exchange (outer sphere) with polyoxometalate takes place within layered double hydroxides, while inner sphere complexes were observed on iron (hydr)oxides, with different geometries according to the structure of the solid surface. The experimental study was supported by vibrational calculations by ab initio DFT, which confirmed the surface geometry of the absorbed species observed by infrared spectroscopy.

This study was undertaken to investigate whether the developing brain adapts at biochemical level against neonatal hypothyroidism, as it does so against a variety of physiological disturbances. A moderate hypothyroid state in mice neonates was induced by supplementing 0.05% methimazole in drinking water to the mothers up to suckling period, and its effect on concerted development of the enzymes regulating metabolic channeling of glucose vis a vis glucose phosphorylating activity were studied. In the brain of control mice, the activity of glucose-6-phosphate dehydrogenase (G6PDH), that channels glucose in biosynthetic route (Pentose phosphate pathway, PPP), increased slightly (∼ 1.3 times) from day1 to 10w age. However, glucose phosphorylating activity and the enzymes that commit glucose for energy production, viz phosphofructokinase1 (PFK1), pyruvate kinase (PK) and lactate dehydrogenase (LDH) showed a progressive postnatal increase to attain their respective adult levels (∼ 5-10 times higher than 1day value) by 3-10w ages of mice. In comparison to the control, in the brain of age matched neonatal hypothyroid mice, glucose phosphorylating activity, G6PDH and PFK1 increased significantly (p<0.001) at day1. Thereafter, though, glucose phosphorylating activity continued to increase up to 1w age and remained static thereafter, G6PDH declined significantly (p<0.001) from 1w onward ages. On the other hand, as PFK1 activity increased significantly up to 10w age (p<0.001), the ratio of G6PDH/PFK1 showed a marked decline from 1w onward ages. PK and LDH also showed increasing trend up to 3w age in the brain of hypothyroid mice pups. The results suggest that a moderate hypothyroid state, during the period of rapid brain growth (day 1-1w age), stimulates all the enzymes that regulate channeling of glucose in both, the energy yielding and biosynthetic paths. However, the later postnatal ages, it modulates these enzymes in a metabolic path dependent manner.

In this work, a high-performance hybrid supercapacitor is assembled with N-doped reduced graphene oxide (N-rGO) decorated with Fe2O3 (Fe2O3/N-rGO) as the anode, and NiCo layered double hydroxide integrated with conductive Co(OH)2 (NiCo LDH/Co(OH)2) as the cathode. The two main pseudo-capacitive materials are modified by different materials (N-rGO and Co(OH)2) to enhance the conductivity. For anode, the Fe2O3 nanoparticles are uniformly dispersed on N-rGO via a facile solvent-thermal method. The highly conductive Fe2O3/N-rGO exhibits a superior capacitance of 912.9F/g at 1 A/g and retains 84% at 30 A/g. The NiCo LDH/Co(OH)2 cathode also synthesized by a convenient solvent-thermal method delivers a high specific capacitance of 2220.0F/g at 1 A/g and retains 70% at a high current density of 50 A/g. Utilizing these electrodes, we successfully fabricate a hybrid battery-like supercapacitor with an excellent energy density of 103.3 Wh/kg at an outstanding power density of 790 W/kg, an excellent capacitance of 296.3F/g at 1 A/g and a remarkable cyclic stability with 92% retention after 1000 cycles at 10 A/g. Due to the elaborately designed electrode materials, the battery-like supercapacitor exhibits excellent electrochemical properties and is an inspiration for future energy storage devices.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19740号 / 工博第4195号 / 新制||工||1647(附属図書館) / 32776 / 京都大学大学院工学研究科分子工学専攻 / (主査)教授 田中 庸裕, 教授 阿部 竜, 教授 陰山 洋 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM