The flexible interrelation between AOX respiratory pathway and photosynthesis in rice leaves.

Alternative respiratory pathway was investigated in rice seedlings grown under total darkness, light/dark cycle, or continuous light. The capacity of the alternative pathway was relatively higher in leaves that had longer light exposure. An analysis of rice AOX1 multigene family revealed that AOX1c, but not AOX1a and AOX1b, had a light-independent expression. The alternative oxidase (AOX) inhibitor, salicylhydroxamic acid (SHAM, 1mM), inhibited nearly 68% of the capacity of the alternative pathway in leaves grown under different light conditions. The plants grown under different light periods were treated with SHAM and then were exposed to illumination for 4h. The transition from dark to 4h of light stimulated the capacity of alternative pathway in etiolated rice seedlings and in those grown under light/dark cycle, whereas the capacity of the alternative pathway was constant in seedlings grown under continuous light with additional 4h of illumination. Etiolated leaves did not show any CO(2) fixation after 4h of illumination, and the increase in chlorophyll content was delayed by the SHAM pretreatment. When seedlings grown under light/dark cycle were moved from dark and exposed to 4h of light, increases in chlorophyll content and CO(2) fixation rate were reduced by SHAM. Although these parameters were stable in plants grown under continuous light, SHAM decreased CO(2) fixation rate but not the chlorophyll content. These results indicate that the role and regulation of AOX in light are determined by the developmental stage of plant photosynthetic apparatus.     

Characterization of fibroblasts recruited from bone marrow-derived precursor in neonatal bronchopulmonary dysplasia mice

We sought to determine whether the extrapulmonary origin of fibroblasts derived from bone marrow (BM) progenitor cells is essential to lung fibrosis in bronchopulmonary dysplasia (BPD). Neonate mice were durably engrafted with BM isolated from transgenic reporter mice that expressed green fluorescent protein (GFP). Such chimera mice were subjected to 60% O(2) exposure for 14 days. A large number of fibroblast-specific protein-1 (FSP1) and GFP-positive fibroblasts were identified in active fibrotic lesions. More surprisingly, however, FSP1(+) fibroblasts also arose in considerable numbers from BM-derived alveolar type II cells (AT2) through epithelial-mesenchymal transition (EMT) during lung fibrogenesis. Cultured lung fibroblasts could express the CXC chemokine receptor (CXCR4) and responded chemotactically to their cognate ligand, chemokine (C-X-C motif) ligand 12 (CXCL12), which were elevated in the serum of BPD mice. These data suggest that lung fibroblasts in BPD fibrosis could variably arise from BM progenitor cells. This finding, which suggests the pathophysiological process of fibrosis, could contribute to a therapy for BPD that is characterized by extensive interstitial fibrosis.     

Relationships between musk extraction, social rank and tail-rubbing in male Alpine musk deer, Moschus sifanicus

Musk deer (Moschus spp.) are small, solitary forest ruminants well-known for the musk secreted by adult males. Because of illegal hunting and habitat degradation and loss, the five species of musk deer are classified as endangered. Musk deer farming has been a positive example of ex situ conservation, maintaining deer numbers whilst sustaining musk production. This study was conducted at the Xinglongshan Musk Deer Farm in Gansu Province in northwest China, and was designed to explore the relationships among musk extraction, fighting ability and social rank in captive, male alpine musk deer (Moschus sifanicus). Results showed that musk production was related to a male’s rank in the dominance hierarchy. Males in the middle rank of the dominance hierarchy tended to produce more musk than deer of higher and lower ranks. This is due to the time-energy budgeting patterns and captive stress of males with different status in the dominance hierarchy. That is, high-ranking males need to budget more time and energy to maintain their higher rank, while low-ranking males are exposed to more aggression from higher-ranking individuals, thus limiting their access to resources such as food and shelter. Accordingly, high-ranking and low-ranking males endured more stress than middle-ranking males, negatively affecting their annual musk production. Supporting the correlation between musk production and the frequency of tail-rubbing behavior was not significant, average musk extraction could not be predicted based on the frequency of tail-rubbing alone. Status in the dominance hierarchy, however, was positively correlated with tail-rubbing frequency, with males of higher rank tending to tail-rub more frequently. Conflict winners tended to initiate tail-rubbing after the conflict; tail-rubbing accounted for 83.33% of the post-conflict behavior expressed by the winner. Tail-rubbing was one of the behavioral rewards of winning a conflict and was also related to releasing aggression; not solely for scent marking territory and trails. Based on the results of this study, there was no direct relationship between musk production and captive males’ status in the dominance hierarchy (and, therefore, in the intensity of aggression displayed). If the sole aim of musk deer farms is to domesticate musk deer for maximum production of musk, we suggest that highly aggressive males be removed from the population. Musk production will remain unchanged, however, aggression level and intensity of fighting could be lessened thus reducing farming costs.     

Miniaturized lensless imaging systems for cell and microorganism visualization in point-of-care testing

Low-cost, robust, and user-friendly diagnostic capabilities at the point-of-care (POC) are critical for treating infectious diseases and preventing their spread in developing countries. Recent advances in micro- and nanoscale technologies have enabled the merger of optical and fluidic technologies (optofluidics) paving the way for cost-effective lensless imaging and diagnosis for POC testing in resource-limited settings. Applications of the emerging lensless imaging technologies include detecting and counting cells of interest, which allows rapid and affordable diagnostic decisions. This review presents the advances in lensless imaging and diagnostic systems, and their potential clinical applications in developing countries. The emerging technologies are reviewed from a POC perspective considering cost effectiveness, portability, sensitivity, throughput and ease of use for resource-limited settings.     

光催化纳米TiO2抗乙型肝炎病毒效果的实验研究

纳米TiO2在光催化下能产生活性羟基,超氧离子(O2-),过氧羟基(·OOH)和过氧化氢,这些产物具有很强的氧化性,因而具有广谱杀菌功能[1].目前国内外已广泛用于陶瓷洁具、玻璃表面、瓷砖釉面、水处理、空气净化等[2～8],但纳米TiO2在光催化下是否具有抗病毒的作用,目前尚未见报道.本文以载有纳米TiO2的陶瓷碟(以下简称纳米瓷碟)和发泡镍网(以下简称纳米镍网)为材料,对纳米TiO2复合材料在不同光源照射下杀灭乙型肝炎病毒(HBV)的效果进行了实验研究,取得了令人满意的结果.     

Matrix metalloproteinase-9 induces cardiac fibroblast migration, collagen and cytokine secretion: inhibition by salvianolic acid B from Salvia miltiorrhiza

Cardiac fibroblasts play the key role in cardiac function and matrix metalloproteinases-9 (MMP-9) is a well known contributor to the development of myocardial remodeling. However, the direct regulation of MMP-9 on the function of cardiac fibroblasts and the underlying mechanism are far from elucidation. In the present research, recombinant protein encoding catalytic domain of MMP-9 (MMP-9 CD) was constructed and the function of neonatal cardiac fibroblasts was investigated by cell proliferation assay, migration assay, picrosirius red assay, multiplex cytokine assay and fibroblast phenotype detection. 200 nM MMP-9 CD stimulated cardiac fibroblasts migration (169.4±22.5% versus 100±0%, p<0.01), increased collagen synthesis (1.5±0.2 fold, p<0.05), up-regulated the secretion of ICAM (574.0±40.1 versus 268.5±8.6pg/ml, p<0.01), TNF-α (192.6±11.0 versus 14.4±1.8pg/ml, p<0.001), IL-6 (1500.9±70.2 versus 323.4±40.6pg/ml, p<0.001) and sVCAM-1 (30.3±4.3 versus 7.0±0.1 pg/ml, p<0.05) and down-regulated VEGF (436.5±148.9 versus 1034.3±28.1 pg/ml, p<0.05) significantly with modest effects on proliferation. Accompanying with these regulations, transition of fibroblasts to myofibroblast was confirmed by immunofluorescent stain of α-smooth muscle actin (α-SMA) with MMP-9 CD treatment. Furthermore, salvianolic acid B (SalB) inhibited the effects of MMP-9 CD significantly. In conclusion, our results provide evidence for a direct influence of MMP-9 on cardiac fibroblast migration, collagen and cytokine secretion, which can be attenuated by SalB.     

中国稻弄蝶属Parnara分类与一新记录种(鳞翅目:弄蝶总科:弄蝶科)

记述中国稻弄蝶属Parnara Moore,18814种,其中圆突稻弄蝶Parnara apostata（Snellen,1866）为1新记录种。制作了分种检索表,进行了新记录种的成虫形态描述,提供了特征图。