The Sod2 gene for Mn-superoxide dismutase (MnSOD), an intramitochondrial free radical scavenging enzyme that is the first line of defense against superoxide produced as a byproduct of oxidative phosphorylation, was inactivated by homologous recombination. Homozygous mutant mice die within the first 10 days of life with a dilated cardiomyopathy, accumulation of lipid in liver and skeletal muscle, and metabolic acidosis. Cytochemical analysis revealed a severe reduction in succinate dehydrogenase (complex II) and aconitase (a TCA cycle enzyme) activities in the heart and, to a lesser extent, in other organs. These findings indicate that MnSOD is required for normal biological function of tissues by maintaining the integrity of mitochondrial enzymes susceptible to direct inactivation by superoxide.

A mouse model for Down syndrome, Ts1Cje, has been developed. This model has made possible a step in the genetic dissection of the learning, behavioral, and neurological abnormalities associated with segmental trisomy for the region of mouse chromosome 16 homologous with the socalled ''Down syndrome region'' of human chromosome segment 21q22. Tests of learning in the Morris water maze and assessment of spontaneous locomotor activity reveal distinct learning and behavioral abnormalities, some of which are indicative of hippocampal dysfunction. The triplicated region in Ts1Cje, from Sod1 to Mx1, is smaller than that in Ts65Dn, another segmental trisomy 16 mouse, and the learning deficits in Ts1Cje are less severe than those in Ts65Dn. In addition, degeneration of basal forebrain cholinergic neurons, which was observed in Ts65Dn, was absent in Ts1Cje.

No abstract

No abstract

electronic devices built on planar substrates, textile electronic devices can be integrated into different materials that fit the curved surface of the human body or other nonplanar surfaces. Besides, it can bear deformations in almost all dimensions, making it applicable for long-term usage as minimal disruption can be made on the comfort and daily activities of the wearers. Another attractive feature of textile electronic devices is that, in principle, they are compatible to the conventional textile technology and can be manufactured on a large scale using the textile manufacturing technique, such as the rollto-roll process.Inspired by the exciting potential applications of textile electronic devices in healthcare, communications, environments, sports, security, and so on, in the past several years, many kinds of textile electronic devices have been produced by researchers all over the world, including sensors, solar cells, thermoelectric power generators and nanogenerators, diodes, transistors, circuits, etc. Ideally, these textile electronic devices would be directly woven into cloth and worn on human body for daily usage. As a result, these devices should be of lightweight, stable performance, and can bear deformations for long-term usage.Flexible textile electronic devices require flexible textile/fiber energy storage devices as compatible power suppliers. To match flexible textile electronic devices, the energy storage devices should have similar textile/fiber shapes with excellent flexibility, mechanical stability, light weight and can also bear deformations in all dimensions. Mainly two types of textile/fiber energy storage devices are explored including fiber lithium-ion batteries (LIBs) and fiber supercapacitors (SCs). [27][28][29][30][31][32][33][34][35][36][37][38][39][40] In recent years, LIBs were successfully made into fiber shapes to fit for flexible textile electronic devices. [41] Unfortunately, relatively complicated procedures are needed to fabricate fiber LIBs. Besides, the power densities of fiber LIBs are still quite low for practical applications. Compared with LIBs, supercapacitors offer higher power delivery capability, faster charge/discharge rates, long cycle livers, and bridging functions for the power-energy gap between traditions dielectric capacitors and batteries. These features make SCs ideal power suppliers for wearable and textile electronics.Over the past decades, researches on fiber SCs expanded very fast and great progresses have been achieved. Although several reviews focusing on some special aspects of fiber SCs Fiber supercapacitors (SCs), with their small size and weight, excellent flexibility and deformability, and high capacitance and power density, are recognized as one of the most robust power supplies available for wearable electronics. They can be woven into breathable textiles or integrated into different functional materials to fit curved surfaces for use in day-to-day life. A comprehensive review on recent important development and progress in fiber SCs is pro...

Carbon nanodots (CDs) have been synthesized at gram scale with a high yield (41.8%) by carbonization of sucrose with oil acid in one simple step. The synthesized CDs are monodisperse with a narrow size distribution (average 1.84 nm in size), and show a high fluorescence quantum yield (21.6%) without passivation. The PL intensity of the obtained CDs is pH independent over a range of 2-8. Besides, their PL intensity remains unchanged even after six hours of UV excitation and six months of storage, exhibiting excellent stability. The obtained CDs have been used for cell imaging. The results demonstrate that the prepared CDs have great potential for real applications.

Sod2-/- mice, which are deficient in the mitochondrial form of superoxide dismutase (MnSOD), have a short survival time that is strongly affected by genetic background. This suggests the existence of genetic modifiers that are capable of modulating the degree of mitochondrial oxidative damage caused by the MnSOD deficiency, thereby altering longevity. To identify these modifier(s), we generated recombinant congenic mice with quantitative trait loci (QTL) containing the putative genetic modifiers on the short-lived C57BL/6J genetic background. MnSOD deficient C57BL/6J mice with a QTL from the distal region of chromosome 13 from DBA/2J were able to survive for as long as those generated on the long-lived DBA/2J background. Within this region, the gene encoding nicotinamide nucleotide transhydrogenase (Nnt) was found to be defective in C57BL/6J mice, and no mature NNT protein could be detected. The forward reaction of NNT, a nuclear-encoded mitochondrial inner membrane protein, couples the generation of NADPH to proton transport and provides NADPH for the regeneration of two important antioxidant compounds, glutathione and thioredoxin, in the mitochondria. This action of NNT could explain its putative protective role in MnSOD-deficient mice.

Two animal models of Down syndrome (human trisomy 21) with segmental trisomy for all (Ts65Dn) or part (Ts1Cje) of human chromosome 21-homologous region of mouse chromosome 16 have cognitive and behavioral abnormalities. To compare these trisomies directly and to assess the phenotypic contribution of the region of difference between them, Ts65Dn, Ts1Cje, and a new segmental trisomic (Ms1Ts65) for the region of difference (App to Sod1) have been generated as littermates and tested in parallel. Although the performance of Ts1Cje mice in the Morris water maze is similar to that of Ts65Dn mice, the reverse probe tests indicate that Ts65Dn is more severely affected. By contrast, the deficits of Ms1Ts65 mice are significantly less severe than those of Ts65Dn. Therefore, whereas triplication of Sod1 to Mx1 plays the major role in causing the abnormalities of Ts65Dn in the Morris water maze, imbalance of App to Sod1 also contributes to the poor performance. Ts65Dn mice are hyperactive and Ts1Cje mice are hypoactive; the activity of Ms1Ts65 mice is not significantly above normal. These findings indicate that genes in the Ms1Ts65 trisomic region must interact with others in the Ts1Cje region to produce hyperactivity in Ts65Dn mice. Although the complex phenotype of DS is believed to result from the overexpression of a large number of genes present on human chromosome 21 (HSA 21) (1, 2), the analysis of individuals with segmental trisomies of HSA 21 has helped to localize some components of the phenotype to subregions of this chromosome (3-5). To permit a more detailed analysis of the relationship between the imbalance of individual genes or chromosome regions and specific phenotypic abnormalities, several animal models of human trisomy 21 have been developed (6 -9). Mice with segmental trisomies of the HSA 21 homologous region on MMU 16 have demonstrated cognitive and behavioral abnormalities (6,8) that are susceptible to genetic dissection. Several laboratories have shown that Ts65Dn mice, with a segmental trisomy extending from proximal of App to Mx1, do not perform as well as controls in the Morris water maze (6, 10, 11). This task, in which the subject has to use visual-spatial cues in the environment to navigate to a platform hidden under the surface of a tank of water, has been repeatedly demonstrated to be sensitive to lesions of the hippocampus in normal animals (12). Another segmentally trisomic mouse, Ts1Cje, is genetically similar to Ts65Dn but does not have triplication of the region from App to Sod1 (Fig. 1). Mice with this trisomy also show impaired performance in the Morris water maze, indicating that segmental trisomy for the distal part of the DS-homologous region of MMU 16 is responsible for hippocampal dysfunction (8). However, because Ts1Cje and Ts65Dn were bred on different genetic backgrounds and different protocols and apparatus were used for behavioral testing, it was not possible to determine whether the phenotype of Ts1Cje, with the smaller region of triplication, differed significantly from that...