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31.
Parasymmetrorbione bicauda n. g., n. sp. is described from Chinese waters infesting two species of Solenocera Lucas (Decapoda: Penaeoidea). The new genus differs from other orbionine genera by the following combination of features: a pronounced asymmetry of coxal and lateral plate development, biramous uropods, tuberculate lateral plates and a digitate internal ridge on oostegite 1. A key to the eight genera of the Orbioninae R. Codreanu, 1967 is presented. Orbione halipori Nierstrasz & Brender à Brandis, 1923 is also recorded from a new Chinese locality and a new host. 相似文献
32.
Lucia Vergauwen Dries Knapen An Hagenaars Gudrun De Boeck Ronny Blust 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2013,183(1):109-121
The zebrafish has become a valuable vertebrate model organism in a wide range of scientific disciplines, but current information concerning the physiological temperature response of adult zebrafish is rather scarce. In this study, zebrafish were experimentally acclimated for 28 days to 18, 26 or 34 °C and a suite of non-invasive and invasive methods was applied to determine the thermal dependence of zebrafish physiological condition. With decreasing temperature, the metabolic rate of zebrafish decreased, as shown by the decreasing oxygen uptake and ammonia excretion rates, limiting the critical swimming speed, probably due to a decreased muscle fibre power output. In response to exercise, fuel stores were mobilized to the liver as shown by the increased hepatosomatic index, liver total absolute energetic value and liver carbohydrate concentration but due to the low metabolic rate they could not be adequately addressed to power swimming activity at 18 °C. Conversely, the increased metabolic performance at high temperature came with an increased metabolic cost resulting in decreased energy status reflected particularly well by the non-invasive condition factor and invasive measures of carcass protein concentration, carcass total absolute energetic value and liver carbohydrate concentration. We showed that the combined measurement of the relative condition factor and critical swimming speed is a powerful non-invasive tool for long-term follow-up studies. Invasive methods were redundant for measuring general energy status but they provided detailed information concerning metabolic reorganization. With this study we proved that the usefulness of the zebrafish as a model organism can easily be expanded to include physiological studies and we provided a reference dataset for the selection of measures of physiological responses for future studies using the zebrafish. 相似文献
33.
Jiachuan Pan Xin Xie Wang Tian Ali Adem Bahar Nan Lin Fangchao Song Jing An Dacheng Ren 《Applied microbiology and biotechnology》2013,97(20):9145-9154
Persisters are a small subpopulation of bacterial cells that are dormant and extremely tolerant to antibiotics. The intrinsic antibiotic tolerance of persisters also facilitates the development of multidrug resistance through acquired mechanisms based on drug resistance genes. In this study, we demonstrate that (Z)-4-bromo-5-(bromomethylene)-3-methylfuran-2(5H)-one (BF8) can reduce persistence during Escherichia coli growth and revert the antibiotic tolerance of its persister cells. The effects of BF8 were more profound when the pH was increased from 6 to 8.5. Although BF8 is a quorum sensing (QS) inhibitor, similar effects were observed for the wild-type E. coli RP437 and its ΔluxS mutant, suggesting that these effects did not occur solely through inhibition of AI-2-mediated QS. In addition to its effects on planktonic persisters, BF8 was also found to disperse RP437 biofilms and to render associated cells more sensitive to ofloxacin. At the doses that are effective against E. coli persister cells, BF8 appeared to be safe to the tested normal mammalian cells in vitro and exhibited no long-term cytotoxicity to normal mouse tissues in vivo. These findings broadened the activities of brominated furanones and shed new light on persister control. 相似文献
34.
H. S. Yoon Y. K. An J. H. Hwang H. S. Lim W. K. Lee K. H. Han S. H. Lee S. D. Choi 《Zeitschrift fur angewandte Ichthyologie》2013,29(2):468-469
Length–weight relationships were estimated for 14 species belonging to 13 fish families from the Suer River estuary, Korea. These 14 species are: Callionymus valenciennei, Konosirus punctatus, Conger myriaster, Cynoglossus joyneri, Tribolodon hakonensis, Thryssa hamiltonii, Acanthogobius flavimanus, Paratrypauchen microcephalus, Hexagrammos agrammus, Nuchequula nuchalis, Pseudopleuronectes yokohamae, Pennahia argentata, Sillago japonica and Takifugu niphobles. Between April 2009 and January 2010, samples were caught by commercial trawl net at depths of <20 m. Estimates for parameter b of the length–weight relationship (W = aLb) ranged between 2.510 and 3.149. 相似文献
35.
36.
Jun Long Xulong Zhang Mingjie Wen Qingli Kong Zhe Lv Yunqing An Xiao-Qing Wei 《Biochemical and biophysical research communications》2013,430(1):364-369
Interleukin (IL)-35 is a novel heterodimeric cytokine in the IL-12 family and is composed of two subunits: Epstein-Barr virus-induced gene 3 (EBI3) and IL-12p35. IL-35 is expressed in T regulatory (Treg) cells and contributes to the immune suppression function of these cells. In contrast, we found that both IL-35 subunits were expressed concurrently in most human cancer cell lines compared to normal cell lines. In addition, we found that TNF-α and IFN-γ stimulation led to increased IL-35 expression in human cancer cells. Furthermore, over-expression of IL-35 in human cancer cells suppressed cell growth in vitro, induced cell cycle arrest at the G1 phase, and mediated robust apoptosis induced by serum starvation, TNF-α, and IFN-γ stimulation through the up-regulation of Fas and concurrent down-regulation of cyclinD1, survivin, and Bcl-2 expression. In conclusion, our results reveal a novel functional role for IL-35 in suppressing cancer activity, inhibiting cancer cell growth, and increasing the apoptosis sensitivity of human cancer cells through the regulation of genes related to the cell cycle and apoptosis. Thus, this research provides new insights into IL-35 function and presents a possible target for the development of novel cancer therapies. 相似文献
37.
Semicontinuous registration of the normal airborne bacteria flora during a one-year period was carried out at an inland and a coastal station near Stockholm. The sampling apparatus were FOA-slitsamplers that work on the impaction principle with a moving solid agar medium as collecting surface. At both localities meteorological variables were also recorded. The concentration of airborne bacteria ranged for the inland station from 0-500 bacteria/m3 with an average of 51 bacteria/m3 and for the coastal station from 0-250 bacteria/m3 with an average of 16 bacteria/m3. The diurnal pattern of variation varies with the time of year but there is a statistical difference between the day-average and night-average for the inland station but not for the coastal station. In the material studied the relative humidity followed by the wind velocity were factors of importance for the variation in the number of viable airborne bacteria. 相似文献
38.
Jian-Hua Liang Wei Lv Xiao-Li Li Kun An Mark Cushman He Wang Ying-Chun Xu 《Bioorganic & medicinal chemistry letters》2013,23(5):1387-1393
We report a series of new 9-oxime ether non-ketolides, including 3-hydroxyl, 3-O-acyl and 3-O-alkyl clarithromycin derivatives, and thiophene-containing ketolides 1b–1d. Unlike previously reported ketolide 1a, none of them is comparable to telithromycin. A molecular modeling study was performed to gain insight into the binding mode of alkylides 17–20 with bacterial rRNA and to rationalize the great disparity of their SAR. The 3-O-sidechains of 19 and 20 point to the so-called hydrophilic side of the macrolide ring, as seen in clarithromycin. In contrast, the 3-O-sidechains of 17 and 18 bend to the backside, the so-called hydrophobic side of the macrolide ring. The results clearly indicated the alkylides with improved antibacterial activity might possess a novel binding mode, which is different from clarithromycin and the alkylides with poor activity. 相似文献
39.