The Potential Role of Hepatocyte Growth Factor in Degenerative Disorders of the Synovial Joint and Spine

This paper aims to provide a comprehensive review of the changing role of hepatocyte growth factor (HGF) signaling in the healthy and diseased synovial joint and spine. HGF is a multifunctional growth factor that, like its specific receptor c-Met, is widely expressed in several bone and joint tissues. HGF has profound effects on cell survival and proliferation, matrix metabolism, inflammatory response, and neurotrophic action. HGF plays an important role in normal bone and cartilage turnover. Changes in HGF/c-Met have also been linked to pathophysiological changes in degenerative joint diseases, such as osteoarthritis (OA) and intervertebral disc degeneration (IDD). A therapeutic role of HGF has been proposed in the regeneration of osteoarticular tissues. HGF also influences bone remodeling and peripheral nerve activity. Studies aimed at elucidating the changing role of HGF/c-Met signaling in OA and IDD at different pathophysiological stages, and their specific molecular mechanisms are needed. Such studies will contribute to safe and effective HGF/c-Met signaling-based treatments for OA and IDD.     

Time-dependent changes in eye-specific segregation in the dorsal lateral geniculate nucleus and superior colliculus of postnatal mice

Eye-specific segregation in the dorsal lateral geniculate nucleus （dLGN） and superior colliculus （SC） starts from the embryonic stage and continues to develop postnatally until eye-opening in mice. However, there have been few systematic studies on the details of this developmental process. Here, we carried out time-dependent studies of eye-specific segregation in the dLGN and SC. Our results demonstrated that the development of eye-specific segregation in the SC is completed before postnatal day 12 （P12）, which is earlier than in the dLGN （P20）. During the whole period, ipsilateral and overlapping axonal projections decreased continuously in both the dLGN and SC. On the other hand, contralateral axonal projections showed little change, except for a slight decrease between P8 and P20 in the dLGN.     

金红石型TiO2(110)表面吸附TiCl4的微观机理

采用密度泛函理论平面波赝势方法研究了TiCl₄分子在TiO₂(110)表面桥位氧上的吸附,对稳定吸附构型的吸附能、电荷密度、差分电荷密度、电子态密度、Mulliken电荷布居等进行计算和分析。研究结果表明,TiCl₄在完整晶胞表面不能吸附;在有氧空位的晶胞表面,TiCl₄以面心向下吸附最稳定,吸附过程为放热。当表面氧空位密度为12.5%、25%时,面心向下吸附方式的吸附能分别为-29.780 9 kJ·mol-1和-48.641 9 kJ·mol-1,表明氧空位密度越高,吸附强度越强;带隙从1.304 eV分别减小到0. 074 eV、0.015 eV,能带结构的带隙宽度变窄,表明氧空位密度越高,带隙宽度越窄;TiCl₄分子向晶胞表面转移的电荷分别为0.2 eV、0.26 eV,说明随着表面氧空位密度增加,TiCl₄分子向晶胞表面转移的电荷量增加,表面对分子的氧化作用越强。     

木糖水解液的中和脱酸工艺研究

采用生产出的中间品木糖水解液为原料,研究了轻质CaCO3中和水解液的工艺条件。实验证明,最佳的工艺条件为温度80℃,加入量为0.005~0.0055 g/mL,加入方式为间歇式加入,保温时间为1~2.5 h。     

Circadian organization and the role of the pineal in birds

All organisms exhibit significant daily rhythms in a myriad of functions from molecular levels to the level of the whole organism. Significantly, most of these rhythms will persist under constant conditions, showing that they are driven by an internal circadian clock. In birds the circadian system is composed of several interacting sites, each of which may contain a circadian clock. These sites include the pineal organ, the suprachiasmatic nucleus (SCN) of the hypothalamus, and, in some species, the eyes. Light is the most powerful entraining stimulus for circadian rhythms and, in birds, light can affect the system via three different pathways: the eyes, the pineal, and extraretinal photoreceptors located in the deep brain. Circadian pacemakers in the pineal and in the eyes of some avian species communicate with the hypothalamic pacemakers via the rhythmic synthesis and release of the hormone melatonin. Often the hypothalamic pacemakers are unable to sustain persistent rhythmicity in constant conditions in the absence of periodic melatonin input from the pineal (or eyes). It has also been proposed that pineal pacemakers may be unable to sustain rhythmicity in constant conditions without periodic neural input from the SCN. Significant variation can occur among birds in the relative roles that the pineal, the SCN, and the eyes play within the circadian system; for example, in the house sparrow pacemakers in the pineal play the predominant role, in the pigeon circadian pacemakers in both the pineal and eyes play a significant role, and in Japanese quail ocular pacemakers play the predominant role.     

Iron oxide nanoparticles decrease nuclear fractal dimension of buccal epithelial cells in a time‐dependent manner

In this paper, we present results that iron oxide nanoparticles (IONPs) induce time‐dependent structural changes in nuclei of buccal epithelial cells. The cells were treated with magnetite, Fe₃O₄ nanoparticles (spherical shape, diameter 80–100 nanometres). The digital micrographs of the nuclei were made in 3 different time points: 15, 30 and 60 min after the treatment with IONPs, as well as in the control cells. A total of 120 nuclear structures (30 per sample) were analysed. Fractal analysis of nuclei was done in ImageJ software of the National Institutes of Health, (Bethesda, MD, USA). For each nuclear structure, the values of fractal dimension and lacunarity were calculated. There was a time‐dependent reduction of nuclear fractal dimension in buccal epithelial cells after exposure to magnetite iron oxide nanoparticles. Negative trend was observed (p < 0.01). Nuclear lacunarity, as another fractal parameter was shown to increase, also in a time‐dependent manner, after the treatment with IONPs. To our knowledge, this is the first study to investigate effects of magnetite nanomaterial on nuclear fractal complexity, and also the first to apply fractal analysis method in testing of the interaction between nanoparticles and cell nucleus in this experimental setting.     

彩南油田采出水处理技术

1996年彩南油田采出水处理系统投产后,出水多项指标达不到注水指标要求,造成废水外排,污染了脆弱的沙漠环境.2004年采用重核-催化强化絮凝净水技术进行改造,其出水水质无需再经过滤处理就能达到<碎屑岩油藏注水水质推荐标准及分析方法>(SY/T 5329-1994)的B2标准,可回注油田.     

Real-time dopamine efflux in the nucleus accumbens core during Pavlovian conditioning.

To assess the role of dopamine input to the nucleus accumbens core in anticipatory learning, fast-scan cyclic voltammetry was combined with appetitive Pavlovian conditioning. One group of rats (Paired) received 16 tone-food pairings for at least four daily sessions while the control group (Unpaired) received the same number of unpaired tone and food presentations. Both groups showed transient dopamine responses during food presentation throughout training, confirming dopamine involvement in reward processing. Only the Paired Group, however, showed consistently timed dopamine transients during the 10-s tone presentation. Transients first appeared near the end of the tone period as each animal acquired the tone-food association and then occurred progressively sooner on subsequent sessions. Later sessions also revealed a consistently timed dopamine response soon after food delivery in Paired animals. Collectively, these results implicate phasic dopamine release in the acquisition of Pavlovian learning and also suggest an early dopamine response to the unconditioned stimulus as training continues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)