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991.
Mengmeng Ma Benjamin D. Anderson Tao Wang Yingan Chen Dingmei Zhang Gregory C. Gray Jiahai Lu 《PloS one》2015,10(5)
During July to September 2014, we performed a controlled, cross-sectional, seroepidemiologic study among 203 swine workers and 115 control subjects in Guangdong Province. Sera were tested using a hemagglutination inhibition assay against locally-isolated swine H3N2 and H1N1 viruses and commercially-obtained human influenza viral antigens. We found swine workers had a greater prevalence and odds of seropositivity against the swine H3N2 virus (17.3% vs. 7.0%; adjusted OR, 3.4; 95% CI, 1.1 -10.7). Younger age, self-report of a respiratory illness during the last 12 months, and seropositivity against seasonal H3N2 virus were identified as significant risk factors for seropositivity against swine H3N2 virus. As swine workers in China may be exposed to novel influenza viruses, it seems prudent for China to conduct special surveillance for such viruses among them. It also seems wise to offer such workers seasonal influenza vaccines with a goal to reduce cross-species influenza virus transmission. 相似文献
992.
The Effect of Long-Term Continuous Cropping of Black Pepper on Soil Bacterial Communities as Determined by 454 Pyrosequencing 总被引:2,自引:0,他引:2
Wu Xiong Zhigang Li Hongjun Liu Chao Xue Ruifu Zhang Huasong Wu Rong Li Qirong Shen 《PloS one》2015,10(8)
In the present study, 3 replanted black pepper orchards with continuously cropping histories for 10, 21, and 55 years in tropical China, were selected for investigating the effect of monoculture on soil physiochemical properties, enzyme activities, bacterial abundance, and bacterial community structures. Results showed long-term continuous cropping led to a significant decline in soil pH, organic matter contents, enzymatic activities, and resulted in a decrease in soil bacterial abundance. 454 pyrosequencing analysis of 16S rRNA genes revealed that the Acidobacteria and Proteobacteria were the main phyla in the replanted black pepper orchard soils, comprising up to 73.82% of the total sequences; the relative abundances of Bacteroidetes and Firmicutes phyla decreased with long-term continuous cropping; and at genus level, the Pseudomonas abundance significantly depleted after 21 years continuous cropping. In addition, bacterial diversity significantly decreased after 55 years black pepper continuous cropping; obvious variations for community structures across the 3 time-scale replanted black pepper orchards were observed, suggesting monoculture duration was the major determinant for bacterial community structure. Overall, continuous cropping during black pepper cultivation led to a significant decline in soil pH, organic matter contents, enzymatic activities, resulted a decrease in soil bacterial abundance, and altered soil microbial community membership and structure, which in turn resulted in black pepper poor growth in the continuous cropping system. 相似文献
993.
Gui-lai Zuo Lian-fang Zhang Jin Qi Hui Kang Peng Jia Hao Chen Xing Shen Lei Guo Han-bing Zhou Jin-shen Wang Qi Zhou Nian-dong Qian Lian-fu Deng 《PloS one》2015,10(3)
The hypoxia-inducible factors (HIFs), HIF-1α and HIF-2α, are the central mediators of the homeostatic response that enables cells to survive and differentiate in low-oxygen conditions. Previous studies indicated that disruption of the von Hippel-Lindau gene (Vhl) coincides with the activation of HIFα signaling. Here we show that inactivation of Vhl in mature osteoblasts/osteocytes induces their apoptosis and disrupts the cell/canalicular network. VHL-deficient (ΔVHL) mice exhibited a significantly increased cortical bone area resulting from enhanced proliferation and osteogenic differentiation of the bone marrow stromal cells (BMSCs) by inducing the expression of β-catenin in the BMSC. Our data suggest that the VHL/HIFα pathway in mature osteoblasts/osteocytes plays a critical role in the bone cell/canalicular network and that the changes of osteocyte morphology/function and cell/canalicular network may unleash the bone formation, The underlying mechanism of which was the accumulation of β-catenin in the osteoblasts/osteoprogenitors of the bone marrow. 相似文献
994.
Zewei Cao Shengxiao Wang Ting Wang Zhizhou Chang Zhenguo Shen 《International journal of phytoremediation》2015,17(3):201-207
This study investigated the anaerobic digestion capability of five plants and the effects of copper (Cu) and S,S’-ethylenediaminedisuccinic acid (EDDS, a chelator widely used in chelant-assisted phytoremediation) on biogas production to determine a feasible disposal method for plants used in remediation. The results showed that in addition to Phytolacca americana L., plants such as Zea mays L., Brassica napus L., Elsholtzia splendens Nakai ex F. Maekawa, and Oenothera biennis L. performed well in biogas production. Among these, O. biennis required the shortest period to finish anaerobic digestion. Compared to normal plants with low Cu content, the plants used in remediation with increased Cu levels (100 mg kg?1) not only promoted anaerobic digestion and required a shorter anaerobic digestion time, but also increased the methane content in biogas. When the Cu content in plants increased to 500, 1000, and 5000 mg kg?1, the cumulative biogas production decreased by 12.3%, 14.6%, and 41.2%, respectively. Studies also found that EDDS conspicuously restrained biogas production from anaerobic digestion. The results suggest that anaerobic digestion has great potential for the disposal of contaminated plants and may provide a solution for the resource utilization of plants used in remediation. 相似文献
995.
The non-selective apoplastic passage of Cu and Cu-citrate complexes into the root stele of monocotyledonous corn and dicotyledonous soybean was investigated using an inorganic-salt-precipitation technique. Either Cu ions or Cu-citrate complexes were drawn into root through the apoplast from the root growth medium, and K4[Fe(CN)6] was subsequently perfused through xylem vessels or the entire root cross section. Based on microscopic identification of the reddish-brown precipitates of copper ferrocyanide in the cell walls of the xylem of corn and soybean roots, Cu2+ passed through the endodermal barrier into the xylem of both species. When the solution containing 200 μM CuSO4 and 400 μM sodium citrate (containing 199.98 μM Cu-citrate, 0.02 μM Cu2+) was drawn via differential pressure gradients into the root xylem while being perfused with K4[Fe(CN)6] through the entire root cross-section, reddish-brown precipitates were observed in the walls of the stele of soybean, but not corn root. However, when a CuSO4 solution containing 0.02 or 0.2 μM free Cu2+ was used, no reddish-brown precipitates were detected in the stele of either of the two plants. Results indicated that endodermis was permeable to Cu-citrate complexes in primary roots of soybean, but not corn. The permeability of the endodermal barrier to the Cu-citrate complex may vary between dicotyledonous and monocotyledonous plants, which has considerable implications for chelant-enhanced phytoextraction. 相似文献
996.
Luminescent properties of Ca3SiO4Cl2 co‐doped with Ce3+ and Eu2+ for near‐ultraviolet light‐emitting diodes
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Ca3SiO4Cl2 co‐doped with Ce3+,Eu2+ was prepared by high temperature reaction. The structure, luminescent properties and the energy transfer process of Ca3SiO4Cl2: Ce3+,Eu2+ were investigated. Eu2+ ions can give enhanced green emission through Ce3+ → Eu2+ energy transfer in these phosphors. The green phosphor Ca2.9775SiO4Cl2:0.0045Ce3+,0.018Eu2+ showed intense green emission with broader excitation in the near‐ultraviolet light range. A green light‐emitting diode (LED) based on this phosphor was made, and bright green light from this green LED could be observed by the naked eye under 20 mA current excitation. Hence it is considered to be a good candidate for the green component of a three‐band white LED. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
997.
David M Albala Jerome B Riebman Richard Kocharian Bogdan Ilie John Albanese Jessica Shen Liza Ovington Jonathan Batiller 《Reviews in urology》2015,17(1):25-30
In the United States, fibrin sealants have been used to achieve hemostasis for nearly two decades. Although their clinical utility was first demonstrated in cardiac surgery, their effectiveness and safety have since been demonstrated to extend to a wide array of procedures. Fibrin sealants typically contain two components—fibrinogen and thrombin—that are combined and delivered simultaneously to a target bleeding site in order to achieve hemostasis. However, many commercial formulations contain other additional components, such as antifibrinolytic agents, that have been associated with adverse outcomes. This subanalysis compares the safety and effectiveness of a fibrin sealant versus an absorbable hemostat for achieving hemostasis during urologic procedures with mild to moderate bleeding.Key words: Hemostasis, Hemostatics, Fibrin tissue adhesive, Urologic surgical procedures, Surgical techniqueIn the United States, fibrin sealants have been used to achieve hemostasis for nearly two decades. Although their clinical utility was first demonstrated in cardiac surgery,1 their effectiveness and safety have since been demonstrated to extend to a wide array of procedures, including cardiovascular, gastrointestinal, pneumothoracic, neurologic, urologic, otolaryngologic, dental, and reconstructive surgeries.2,3 Within the field of urology, fibrin sealants have been used to manage bleeding from renal trauma,4 as well as to facilitate hemostasis during renal surgeries, including partial nephrectomies.5–7Fibrin sealants typically contain two components—fibrinogen and thrombin—that are combined and delivered simultaneously to a target bleeding site (TBS) in order to achieve hemostasis.3 Many commercial formulations contain other additional components, such as antifibrinolytic agents, that have been associated with adverse outcomes. For example, in an observational study (N = 4374), the antifibrinolytic aprotinin was associated with an increased risk of long-term mortality within 5 years following coronary artery bypass graft surgery.8 Furthermore, repeated exposure to aprotinin may lead to allergic or potentially fatal anaphylactic reactions.9–11 For this reason, the US Food and Drug Administration (FDA) issued an alert in 2006 indicating that caution should be used when using aprotinin in patients with a history of previous exposure to the product.12 Tranexamic acid, another antifibrinolytic present in some commercial fibrin sealants, has been associated with alterations in neural tissue growth and adherence.13 Because of the risk of cerebral neurologic toxicity, fibrin sealants containing tranexamic acid are contraindicated for use in neurosurgery or in surgical procedures during which contact with cerebrospinal fluid or dura mater may occur.14In a phase III, randomized, single-blind, parallel-group, multicenter study,15 the fibrin sealant CROSSEAL™ (Ethicon, Inc., Somerville, NJ) significantly reduced the time to hemostasis during liver resection surgery compared with conventional hemostatic techniques. EVICEL® Fibrin Sealant (Human) (Ethicon, Inc.), the successor of CROSSEAL, requires no antifibrinolytic additive and is therefore both aprotinin and tranexamic acid free, and achieves hemostasis using exclusively human components.16 The effectiveness and safety of this fibrin sealant for hemostasis in soft tissue during elective retroperitoneal or intra-abdominal surgery were compared with an absorbable hemostat (SURGICEL® Absorbable Hemostat; Ethicon, Inc.) in a randomized, active-controlled, multicenter study.17 This article describes a subanalysis of data from the largest patient subgroup from that study, and evaluates the effectiveness and safety of a fibrin sealant versus an absorbable hemostat for patients who underwent urologic surgical procedures. 相似文献
998.
999.
Yao-An Shen Chia-Yu Wang Yi-Tao Hsieh Yann-Jang Chen Yau-Huei Wei 《Cell cycle (Georgetown, Tex.)》2015,14(1):86-98
Cancer stem cells (CSCs) represent a subpopulation of tumor cells endowed with
self-renewal capacity and are considered as an underlying cause of tumor recurrence and
metastasis. The metabolic signatures of CSCs and the mechanisms involved in the regulation
of their stem cell-like properties still remain elusive. We utilized nasopharyngeal
carcinoma (NPC) CSCs as a model to dissect their metabolic signatures and found that CSCs
underwent metabolic shift and mitochondrial resetting distinguished from their
differentiated counterparts. In metabolic shift, CSCs showed a greater reliance on
glycolysis for energy supply compared with the parental cells. In mitochondrial resetting,
the quantity and function of mitochondria of CSCs were modulated by the biogenesis of the
organelles, and the round-shaped mitochondria were distributed in a peri-nuclear manner
similar to those seen in the stem cells. In addition, we blocked the glycolytic pathway,
increased the ROS levels, and depolarized mitochondrial membranes of CSCs, respectively,
and examined the effects of these metabolic factors on CSC properties. Intriguingly, the
properties of CSCs were curbed when we redirected the quintessential metabolic
reprogramming, which indicates that the plasticity of energy metabolism regulated the
balance between acquisition and loss of the stemness status. Taken together, we suggest
that metabolic reprogramming is critical for CSCs to sustain self-renewal, deter from
differentiation and enhance the antioxidant defense mechanism. Characterization of
metabolic reprogramming governing CSC properties is paramount to the design of novel
therapeutic strategies through metabolic intervention of CSCs. 相似文献