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Lu Chen  Shuqiang Li  Zhe Zhao 《ZooKeys》2015,(541):41-56
One new genus of the spider subfamily Coelotinae, Flexicoelotes gen. n., with five new species is described from southern China: Flexicoelotes huyunensis sp. n. (female), Flexicoelotes jiaohanyanensis sp. n. (male and female), Flexicoelotes jinlongyanensis sp. n. (male and female), Flexicoelotes pingzhaiensis sp. n. (female), Flexicoelotes xingwangensis sp. n. (male and female).  相似文献   
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Caesalpinia platyloba was evaluated as an alternative for the retention of atmospheric carbon and as a feasible and viable economic activity in terms of income for tropical deciduous forest (TDF) peasants in the carbon markets. A total of 110 trees of C. platyloba from plantations and a TDF in the Northwest of Mexico were sampled. Growth (increase in height, diameter, and volume curves) was adjusted to assess their growth. Growth of individuals (height, diameter at breast height [DBH], age, and tree crown cover) was recorded. The Schumacher model (H = β0eβ1E-1), by means of the guided curve method, was used to adjust growth models. Information analysis was made through the non-linear procedure with the multivariate secant or false position (DUD) method using the SAS software. Growth and increase models revealed acceptable adjustments (pseudo R2>0.8). C. platyloba reaches >8m of height with 12cm in diameter and 550cm3 of volume, presenting the highest increase at 11 years considered as basal age. Highest significant density of wood was in good quality sites (0.80g•cm-3), with a carbon content (average of 99.15tC•ha-1) at the highest density of 2500 trees•ha-1 (without thinning). Average incomes of US$483.33tC•ha-1 are expected. The profitability values (NPW = US$81,646.65, IRR = 472%, and B/C = 0.82) for C. platyloba make its cultivation a viable and profitable activity, considering a management scheme of the income derived from wood selling and from carbon credits.  相似文献   
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Cellulases are the key enzymes used in the biofuel industry. A typical cellulase contains a catalytic domain connected to a carbohydrate-binding module (CBM) through a flexible linker. Here we report the structure of an atypical trimodular cellulase which harbors a catalytic domain, a CBM46 domain and a rigid CBM_X domain between them. The catalytic domain shows the features of GH5 family, while the CBM46 domain has a sandwich-like structure. The catalytic domain and the CBM46 domain form an extended substrate binding cleft, within which several tryptophan residues are well exposed. Mutagenesis assays indicate that these residues are essential for the enzymatic activities. Gel affinity electrophoresis shows that these tryptophan residues are involved in the polysaccharide substrate binding. Also, electrostatic potential analysis indicates that almost the entire solvent accessible surface of CelB is negatively charged, which is consistent with the halophilic nature of this enzyme.  相似文献   
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Mammalian target of rapamycin (mTOR) regulates cell growth, cell differentiation and protein synthesis. Rapamycin, an inhibitor of mTOR, has been widely used as an immunosuppressant and anti-cancer drug. Recently, mTOR inhibitors have also been reported to be a potential anti-epileptic drug, which may be effective when used in young patients with genetic epilepsy. Thus, a suitable dose of rapamycin which can maintain the normal function of mTOR and has fewer side effects ideally should be identified. In the present study, we first detected changes in marker proteins of mTOR signaling pathway during development. Then we determined the dose of rapamycin by treating rats of 2 weeks of age with different doses of rapamycin for 3 days and detected its effect on mTOR pathway. Young rats were then treated with a suitable dose of rapamycin for 4 weeks and the effect of rapamycin on mTOR, development and immunity were investigated. We found that the expression of the marker proteins of mTOR pathway was changed during development in brain hippocampus and neocortex. After 3 days of treanent, 0.03 mg/kg rapamycin had no effect on phospho-S6, whereas 0.1, 0.3, 1.0 and 3.0 mg/kg rapamycin inhibited phospho-S6 in a dose-dependent manner. However, only 1.0 mg/kg and 3.0 mg/kg rapamycin inhibited phospho-S6 after 4 weeks treatment of rapamycin. Parallel to this result, rats treated with 0.1 and 0.3 mg/kg rapamycin had no obvious adverse effects, whereas rats treated with 1.0 and 3.0 mg/kg rapamycin showed significant decreases in body, spleen and thymus weight. Additionally, rats treated with 1.0 and 3.0 mg/kg rapamycin exhibited cognitive impairment and anxiety as evident by maze and open field experiments. Furthermore, the content of IL-1β, IL-2, IFN-γ, TNF-α in serum and cerebral cortex were significantly decreased in 1.0 and 3.0 mg/kg rapamycin-treated rats. The expression of DCX was also significantly decreased in 1.0 and 3.0 mg/kg rapamycin-treated rats. However, rats treated with 1.0 mg/ kg rapamycin exhibited fewer and milder side effects than those treated with 3.0 mg/kg. In summary, all these data suggest that there is not a rapamycin dose that can inhibit mTOR for epilepsy without causing any side effects, but 1 mg /kg may be the optimal dose for young rats for suppressing mTOR with relatively few side effects.  相似文献   
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The translocation of the 325 leftmost bp of the genome of pseudorabies virus (PrV) to the internal junction between the L and S components confers upon the virus a growth advantage relative to wild-type PrV in chicken embryo fibroblasts (CEFs) and chickens and a growth disadvantage in rabbit kidney (RK) cells and mice. To clarify the molecular basis for the species-specific growth characteristics of the translocation mutants, we have compared several parameters of the virus growth cycle in CEFs and RK cells infected with wild-type PrV and with translocation mutants. The salient findings are as follows. (i) The synthesis of early-late and late proteins is not as effective in CEFs as it is in RK cells, and these proteins, in particular, the major capsid proteins, accumulate less abundantly in CEFs than in RK cells. (ii) Cleavage of concatemeric DNA to genome-size molecules is also not as effective in CEFs as it is in RK cells. (iii) The internal junction present in translocation mutants is a functional cleavage site. (iv) In RK cells, translocation mutants are hypercleaved and a significant proportion of the total viral DNA is cleaved into subgenomic fragments. (v) In CEFs infected with translocation mutants, subgenomic fragments also accumulate but most of the viral DNA remains in concatemeric form. A model which postulates that the cell-specific growth advantage or disadvantage of the translocation mutants is related to the presence of a second cleavage site within their genomes and is affected by the efficiency of cleavage of concatemeric DNA in particular infected cell types is presented. The significance of these findings as they relate to the evolution of herpesviruses with class 2- and class 3-like genomes is discussed.  相似文献   
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MicroRNAs (miRNAs) regulate the progression of human malignancy by targeting oncogenes or tumor suppressors, which are 12 promising targets for cancer treatment. Increasing evidence has suggested the aberrant expression and tumor-suppressive function of miR-1298 in cancers, however, the regulatory mechanism of miR-1298 in breast cancer (BC) remains unclear. Here, our findings showed that miR-1298 was down-regulated in BC tissues and cell lines. Lower level of miR-1298 was significantly correlated with the advanced progression of BC patients. Experimental study showed that overexpression of miR-1298 inhibited the proliferation, induced apoptosis and cell cycle arrest in BC cells. The in vivo xenograft mice model showed that highly expressed miR-1298 significantly reduced the tumor growth and metastasis. Further mechanism analysis revealed that miR-1298 bound the 3′-untranslated region (UTR) of a disintegrin and metalloproteinase 9 domain (ADAM9) and suppressed the expression of ADAM9 in BC cells. ADAM9 was overexpressed in BC tissues and inversely correlated with miR-1298. Down-regulation of ADAM9 induced apoptosis and cell cycle arrest of BC cells. Moreover, ectopic expression of ADAM9 by transiently transfecting with vector encoding the full coding sequence of ADAM9 attenuated the inhibitory effects of miR-1298 on the proliferation and cell cycle progression of BC cells. Collectively, our results illustrated that miR-1298 played a suppressive role in regulating the phenotype of BC cells through directly repressing ADAM9, suggesting the potential application of miR-1298 in the therapy of BC.  相似文献   
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Wu  Haitao  Guan  Qiang  Lu  Kangle  Batzer  Darold P. 《Hydrobiologia》2019,832(1):153-174
Hydrobiologia - Lake Malaŵi cichlids have evolved rapidly, extensively, and in some cases iteratively to fill an array of ecological niches; however, neither species richness nor trophic...  相似文献   
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