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51.
It is generally accepted that children with attention-deficit/hyperactivity disorder (ADHD) have poor motor control, especially in bimanual coordination tasks. Such children characteristically have impaired fine motor ability, problems with force control, and poor motor coordination. They are at particular risk of loss of motor control and reduced bimanual coordination. We tested whether, compared to a control condition, neurofeedback training (NFT) could improve bimanual coordination among children with ADHD. 20 Children with ADHD (mean age 7.9 years; SD 2.11) were randomly assigned either to NFT or to a control condition. All participants completed a bimanual coordination test at the following time points: baseline, assessment 1, assessment 2, assessment 3, and again 12 session later at posttest. NFT consisted of Sensory Motor Rhythm (SMR) training to achieve increased SMR in C3 and C4, while participants in the control condition were under mock NFT conditions. Bimanual coordination accuracy and consistency improved from baseline to completion of the intervention (significant Time effect), but in the NFT condition (significant time?×?group interaction). Compared to the control condition, the NFT group had fewer errors in both patterns of bimanual coordination (significant Group effect). Among children with ADHD, SMR neurofeedback training (NFT) led to significant improvements in a bimanual coordination task. The SMR NFT thus appears to have the potential to improve and enhance the motor control of ADHD patients.  相似文献   
52.
Despite the effectiveness of renin-angiotensin blockade in retarding diabetic nephropathy progression, a considerable number of patients still develop end-stage renal disease. The present investigation aims to evaluate the protective potential of FPS-ZM1, a selective inhibitor of receptor for advanced glycation end products (RAGE), alone and in combination with valsartan, an angiotensin receptor blocker, against glomerular injury parameters in streptozotocin-induced diabetic rats. FPS-ZM1 at 1 mg/kg (i.p.), valsartan at 100 mg/kg (p.o.), and their combination were administered for 4 weeks, starting 2 months after diabetes induction in rats. Tests for kidney function, glomerular filtration barrier, and podocyte slit diaphragm integrities were performed. Combined FPS-ZM1/valsartan attenuated diabetes-induced elevations in renal levels of RAGE and phosphorylated NF-κB p65 subunit. It ameliorated glomerular injury due to diabetes by increasing glomerular nephrin and synaptopodin expressions, mitigating renal integrin-linked kinase (ILK) levels, and lowering urinary albumin, collagen type IV, and podocin excretions. FPS-ZM1 also improved renal function as demonstrated by decreasing levels of serum cystatin C. Additionally, the combination also alleviated indices of renal inflammation as revealed by decreased renal monocyte chemoattractant protein 1 (MCP-1) and chemokine (C-X-C motif) ligand 12 (CXCL12) expressions, F4/80-positive macrophages, glomerular TUNEL-positive cells, and urinary alpha-1-acid glycoprotein (AGP) levels. These findings underline the benefits of FPS-ZM1 added to valsartan in alleviating renal glomerular injury evoked by diabetes in streptozotocin rats and suggest FPS-ZM1 as a new potential adjunct to the conventional renin-angiotensin blockade.  相似文献   
53.

Background and aims

The current study was undertaken to investigate the mechanism underlying Boron (B)-alleviated phosphate (P) deficiency in Arabidopsis thaliana. Furthermore, we were interested to explore whether this alleviation of P deficiency by B could extend to Brassica crops.

Methods

Arabidopsis thaliana or Brassica oleracea plants were grown under P-sufficient or -deficient condition with or without extra B for 7 days, then shoots and roots of B. oleracea were sampled for analysis of soluble P content while those of A. thaliana were harvested for analysis of total P content, soluble P content and nitric oxide (NO) as well as for cell wall extraction and RNA isolation.

Results

A. thaliana plants showed reduced root growth and decreased P content in the root under P-deficient conditions, but improved root growth when supplemented with additional B. Further analysis revealed that exogenous B elevated the cell wall pectin content and facilitated the release of P in P-deficient seedlings, thus more soluble P was available to sustain growth under P deficiency. Furthermore, B supplement also increased soluble P in P-deficient cabbage (Brassica oleracea var. capitata L.), an economically important vegetable crop. P deficiency alone was sufficient to induce NO accumulation, and in combination with B application further enhanced NO accumulation, while exogenous application of NO scavenger c-PTIO [2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide] counteracted this positive effect of B, indicating that NO is positively involved in B-mediated alleviation of P deficiency.

Conclusions

Our study reveals the critical role of B in improving the growth of P-deficient plants, and also provides evidence implicating the involvement of NO signal.
  相似文献   
54.
Protein glycation has been implicated to play an important role in the pathogenesis of Alzheimer’s disease and other neurological disorders. Glycation induces extensive change in the structure of proteins and leads to the formation of cross β-structures which are detected by the receptor of AGE. Activation of these receptors by glycated proteins transduces the signaling pathways which contribute to neuronal malfunctions and death. Glycated proteins can induce activation of microglia, which exacerbate the pathology of Alzheimer’s disease by causing chronic inflammation. Compounds which can decelerate glycation or prevent the structural change of proteins during glycation should be of therapeutic interest. In this study the effect of nicotine on protein glycation and structural alterations of the glycated protein were investigated. Bovine serum albumin, as a model protein, was glycated by glucose in the presence or absence of nicotine and structural changes in the protein together with the effect of glycated proteins on the activation of microglia via receptor of AGE were studied. Nicotine not only could not prevent glycation, but even increased protein glycation. However, proteins glycated in the presence of nicotine did not form β-structures. In the absence of this secondary structure glycated proteins cannot bind to the receptor of AGE on microglia. Here we showed that glycated proteins prepared in the presence of nicotine could not activate microglial cells.  相似文献   
55.
56.
UV radiation of the skin impairs immune responses to haptens and to tumor Ags. Transcutaneous immunization (TCI) is an effective method of inducing immune responses to protein and peptide Ag. We explore the effect of UV irradiation on TCI. The generation of Ag-specific CTL to OVA protein, but not class I MHC-restricted OVA peptide, is inhibited by TCI through UV-irradiated skin. Consequently, the induction of protein contact hypersensitivity and in vivo Ag-specific CTL activity following OVA protein immunization is prevented. Application of haptens to UV-exposed skin induces hapten-specific tolerance. We demonstrate that application of protein or class II MHC-restricted OVA peptide to UV-irradiated skin induces transferable Ag-specific tolerance. This tolerance is mediated by CD4(+)CD25(+) T regulatory (T(reg)) cells. These Ag-specific T(reg) cells inhibit the priming of CTL following protein immunization in the presence of CpG adjuvant. IL-10 deficiency is known to prevent hapten-specific tolerance induction. In this study, we demonstrate, using IL-10-deficient mice and adoptive T cell transfer, that IL-10 is required for the direct inhibition of CTL priming following immunization through UV-irradiated skin. However, IL-10 is not required for the induction of T(reg) cells through UV-irradiated skin as IL-10-deficient T(reg) cells are able to mediate tolerance. Rather, host-derived IL-10 is required for the function of UV-generated T(reg) cells. These experiments indicate that protein and peptide TCI through UV-irradiated skin may be used to induce robust Ag-specific tolerance to neo-Ags and that UV-induced T(reg) cells mediate their effects in part through the modulation of IL-10.  相似文献   
57.
58.
In this study, based on behavioral and neurophysiological facts, a new hierarchical multi-agent architecture is proposed to model the human motor control system. Performance of the proposed structure is investigated by simulating the control of sit to stand movement. To develop the model, concepts of mixture of experts, modular structure, and some aspects of equilibrium point hypothesis were brought together. We have called this architecture MODularized Experts Model (MODEM). Human motor system is modeled at the joint torque level and the role of the muscles has been embedded in the function of the joint compliance characteristics. The input to the motor system, i.e., the central command, is the reciprocal command. At the lower level, there are several experts to generate the central command to control the task according to the details of the movement. The number of experts depends on the task to be performed. At the higher level, a “gate selector” block selects the suitable subordinate expert considering the context of the task. Each expert consists of a main controller and a predictor as well as several auxiliary modules. The main controller of an expert learns to control the performance of a given task by generating appropriate central commands under given conditions and/or constraints. The auxiliary modules of this expert learn to scrutinize the generated central command by the main controller. Auxiliary modules increase their intervention to correct the central command if the movement error is increased due to an external disturbance. Each auxiliary module acts autonomously and can be interpreted as an agent. Each agent is responsible for one joint and, therefore, the number of the agents of each expert is equal to the number of joints. Our results indicate that this architecture is robust against external disturbances, signal-dependent noise in sensory information, and changes in the environment. We also discuss the neurophysiological and behavioral basis of the proposed model (MODEM).  相似文献   
59.
The present study demonstrates the comparative thermal, conformational and kinetic stabilities of the three closely related enzymes; the mesophilic yeast alcohol dehydrogenase (YADH), horse liver alcohol dehydrogenase (HLADH), and the extreme-thermophilic Thermoanaerobacter brockii alcohol dehydrogenase (TBADH). The mid-point unfolding temperatures for TBADH and HLADH were at least 10 °C and 6 °C higher, respectively, than that of YADH. When YADH was completely inactivated by thermal stress, the residual activities of HLADH and TBADH were 70% and 100%, respectively. The optimum temperature (Topt) activities of HLADH and TBADH were at least 40 °C and 55 °C higher, respectively, than that of YADH. Due to the higher rigidity of HLADH and TBADH, the enzymatic activation energies of HLADH and TBADH were higher than that of YADH. Geometric X-ray analysis indicated a comparatively higher coil (turn and loop) percentage in TBADH and HLADH than in YADH. Pairwise alignment for TBADH/HLADH exhibited a similarity score approximately 2.5-fold greater than that of the TBADH/YADH pair. Multiple alignments made with ClustalW revealed a higher number of conserved proline residues in the two most stable enzymes (HLADH/TBADH). These extra prolines tend to occur in surface loops and are likely to be responsible for the increased stability of TBADH and HLADH, by loop rigidification.  相似文献   
60.
A total of 486 specimens of Scardinius erythrophthalmus caught in the Anzali lagoon, a large lagoon located in the southwest Caspian Sea (Iran), between March and June 2007 were examined. Age determination showed that the maximum ages observed were 4+ in males and 5+ in females. Isometric growth was identified from length-weight relationship in males, females and pooled data. There was no significant difference from parity in the overall sex ratio of 252 males to 234 females. The fish spawn from mid April to late May, with peak spawning in mid May with the highest average GSI value of 7.12 and 13.52 for males and females respectively. The absolute fecundity ranged between 1482–59620 eggs with the mean of 9287.87 eggs while relative fecundity ranged from 127.8 to 1737.6 eggs/g with the average of 709 eggs/g of body weight. Egg diameter ranged from 0.43 to 1.23 mm with a mean of 0.73 mm. The characteristics of rudd in the stunted population from the Anzali lagoon differ markedly from those of other localities of its range.  相似文献   
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